The BBC's team of correspondents logs its reports and personal impressions as the turmoil surrounding the disputed results of Iran's presidential elections continues.
MARCUS GEORGE, LONDON , 1710 GMT (Sunday)
Jon Leyne has been the BBC's Tehran correspondent for the last two years and he was due to stay for one more. But this afternoon the BBC confirmed that he had been told to leave the country.
The reasons for this aren't known. Whatever they may be, Iran's leadership has eyed the BBC with increasing suspicion since the launch of BBC Persian-language television in January.
The expulsion ends a week of relentless pressure on journalists. On Tuesday, the authorities imposed severe restrictions, barring foreign journalists from covering the opposition's daily protests against the election result. And throughout the week, broadcasts by international news networks to Iran - including the BBC's - have been jammed and their websites blocked.
Domestic media have also come under extreme pressure. According to one campaign group, more than 20 prominent Iranian journalists and bloggers have been arrested. Several opposition newspapers have also been closed down.
Before the election, Iran was known as a difficult place to work for journalists. Now, those challenges have become even greater.
JEREMY BOWEN, TEHRAN, 1635 GMT
The strong show of force for a second day meant that there were no demonstrators on the streets but that doesn't mean the crisis is over. Far from it. The splits in the country and in the leadership are too deep for that.
Neither side shows any sign of giving in. The Supreme Leader Ayatollah Khamenei has demanded that all the Iranian people accept an election result he insists was fair.
The violence on the streets has sharpened the message coming from Mir Hossein Mousavi who believes he was cheated of victory. He's sounding more and more certain of his ground. In a manifesto on his website, he's called for the election to be annulled, for free speech and for fundamental reform to create a new kind of politics in the Islamic republic.
It all adds up to an unprecedented direct challenge to the Supreme Leader himself.
JEREMY BOWEN, TEHRAN, 1310 GMT
A news agency here is reporting that the daughter of former President Hashemi Rafsanjani has been arrested. She'd been filmed addressing demonstrators. Mr Rafsanjani, who is one of the most influential figures in Iran, is an opponent of President Ahmadinejad.
He's been silent during this crisis, but it's certain he's active behind the scenes.
Mr Rafsanjani did not go to the prayer session in which Iran's Supreme Leader Ayatollah Khamenei made a very tough speech endorsing the election result and saying that opposition leaders would be responsible for any bloodshed.
That was another sign of the fracture in the leadership of this country.
JEREMY BOWEN, TEHRAN, 1115 GMT
There seems to be an expectation based on things that we're hearing here that there will be more demonstrations later on today, and that means that perhaps the pattern of yesterday might be repeated.
I think that what's important is that there's a split at the top of the country, that both sets of leaders on either side are digging in their heels about this, and that's then mirrored by the split on the streets between those people who really think the election was a fraud and people who don't.
There's a warning that people might be detained, there's a warning that they might be accused of being terrorists in the pay of foreign powers, and there's a warning as well that there could be more bloodshed.
JEREMY BOWEN, TEHRAN, 1010 GMT
Iran has continued to blame foreign powers for meddling in its affairs. Britain has been accused of that and so has the United States.
President Obama has made his strongest comment so far on the crisis. His calls for the Iranian Government to stop what he called all violent and unjust actions against its people reflect the pressure he's under at home to condemn what's happening here.
He doesn't want to do anything that will undermine his strategy of trying to negotiate with Iran, especially about its nuclear plans, but he's finding out that events in this part of the world often move faster than diplomacy.
JEREMY BOWEN, TEHRAN, 0600 GMT
State television in Iran has reported that members of an opposition group have been arrested, allegedly for what were described as terrorist activities.
The report said they were taking orders from their operations room in Britain. The speaker of the parliament, Ali Larijani, has accused Britain and the United States of meddling in Iran's affairs.
Official Iran's suspicion of the actions of foreigners will be deepened by President Obama's strongest comments so far on the crisis.
Mr Obama doesn't want to do anything that will undermine his strategy of trying to negotiate with Iran, especially about its nuclear plans. But he's finding out that events in this part of the world often move faster than diplomacy.
A BBC CORRESPONDENT, TEHRAN, 1900 GMT (Saturday)
We have this daily cry now from the roofs of Allahu Akhbar - God is Great - it's an opposition protest and night after night it seems to get louder and longer.
Tonight was the loudest and longest I've heard, and that really symbolises and shows you the mood of the opposition here.
Whatever happens, whatever the government is putting up against them, they seem more and more determined to press on.
A BBC CORRESPONDENT, TEHRAN, 1540 GMT
At first it looked as though the government's tactics had worked. Thousands of police, militiamen and secret policemen blocked off the streets leading to the two main squares, Enghelab and Azadi, where the demonstrators had been planning to hold their gatherings.
All they could do instead was to wander along the streets aimlessly, not even daring at first to chant or shout.
But the police couldn't be everywhere and halfway along the avenue leading from one of the squares to the other, I watched a crowd slowly gather and begin chanting, setting fire to rubbish bins and throwing stones at the police.
They had achieved the critical mass they needed and more and more demonstrators joined them. Near me in the crowd a man was shot in the arm and the air was thick with tear gas.
I saw another man whose arm had been slashed by a razor wielded by a secret policeman. The confrontations are still going on and a big column of black smoke from a fire is hanging over the city centre.
A BBC CORRESPONDENT, TEHRAN, 1320 GMT
I'm in the centre of Tehran close to Enghelab Square, where the demonstration was supposed to have been held. But there's a huge security presence here, thousands of men from every possible service: police, Revolutionary Guard, military police, the riot police in full riot gear, and the much-feared basiji - religious paramilitaries who see themselves as the shock troops of the Islamic revolution.
It's impossible for any groups of people to get through these to Enghelab Square and hold their demonstration.
If this continues and the opposition can't find some way around the fierce security then the protests against the results of the presidential election will have been defeated, at least for the time being.
The real strength of the protest has been its ability to get huge numbers of people together into the streets.
Now, the government has trumped that and shown it has the power to lock down the city centre and regain the streets.
JON LEYNE, TEHRAN, 1200 GMT
The situation is very tense and very confused. We don't have direct, immediate reports from the scene because of course we're not allowed to go there.
It's not even entirely clear whether the opposition wanted the demonstration to go ahead. There were a lot of mixed messages through the day whether or not it had been called off. My instinct is that I think opposition supporters are so fired up, they're going to turn up anyway.
They've been very good at getting messages between themselves very quickly, so it's possible they might move the demonstration if there are riot police in the planned location.
The Guardian Council, the body that is overseeing this election, has recounted 10% of the ballots, a random 10% chosen in the presence of the candidates or the candidates' representatives.
However, yesterday the Supreme Leader said it was finished, there was no more dispute over the election. The Guardian Council is loyal to him, so I don't think the candidates have any great faith in this legal process.
Two of the candidates - Mehdi Karroubi and Mir Hossein Mousavi didn't even turn up to a scheduled meeting with the Guardian Council today, so I think the process of conciliation is really over now.
JON LEYNE, TEHRAN, 1100 GMT
We are waiting to see, crucially, whether a planned opposition rally goes ahead this afternoon, in defiance of the Supreme Leader's tough warning. My view is that it is so late now, opposition supporters will turn up anyway, whatever their leaders say.
It is a very confused and tense situation. The security forces are out on the streets. They have been issuing dire warnings that they will deal with any unauthorised demonstrations with determination.
President Mahmoud Ahmadinejad has hardly been heard from in the last few days. This is all about the position of the Supreme Leader. Any rally, particularly if it is attended by the opposition leaders, would be the most direct challenge to his authority. If it goes ahead and there is a large crowd, that would be a massive challenge to him. If it goes ahead and it is broken up with violent force, that could also damage his position enormously.
It is a very, very tense situation. There are huge political issues at stake, if not even the future of the Islamic Republic.
JON LEYNE, TEHRAN, 1000 GMT
My feeling is that whatever Mir Hossein Mousavi says, the people will gather for this demonstration. There is a remote possibility that he might call it off but all the indications are that it will go ahead. Mr Mousavi will turn up, as will defeated candidate Mehdi Karroubi and former President Khatami.
I have heard there is a substantial security presence on the streets of Tehran. This really is looking like the big showdown
Mr Mousavi and Mr Karroubi showed what they thought of the offer of a vote recount by not even turning for their meeting with the Guardian Council, according to state television. They have apparently lost faith in the legal appeals process. After all, the Supreme Leader himself has announced that the result is absolutely right and a body so loyal to him as the Guardian Council is not about to overturn it. It is clear now that the battle, or at least the argument, will go on to the street.
I have heard increasing numbers of opposition people say, "I would rather die than live in the country the way it is now". That is the mood they are in. They are determined to go out there. We will have to wait and see, with some trepidation, what will go on today.
This is a bitter fight for control of this country. Although nobody is saying as much, it really could threaten the existence of the Islamic Republic. This is a battle for control of this country, right to the very top. It is hard to see how the opposition could possibly win this battle without the Supreme Leader being toppled from power, and that in itself would put grave doubts on the whole basis of the system. No wonder both sides are fighting to the last man.
JON LEYNE, TEHRAN, 0900 GMT
The opposition leader Mir Hussein Musavi has not made the direct statement himself but his wife, Zahra Rahnavard - who has played a key role in his campaign - has said on her facebook site that the rally is going ahead.
If so, this will be the most direct challenge to the authority of the Supreme Leader Ayatollah Ali Khamenei.
A huge turnout is expected. Iran and the world will be watching to see how the Iranian security forces respond.
The position of the leader himself is beginning to look under threat.
JON LEYNE, TEHRAN, 0600 GMT
It is still not clear whether the opposition are going to go ahead with a protest called for this afternoon or whether they are going to call it off. There has been no firm word yet either from Mr Mousavi, the main opposition leader, or from Mehdi Karroubi, the other main opposition figure, as to whether they want the demonstration to go ahead.
The National Security Council of Iran has issued another warning to Mr Mousavi, saying that if he provokes an "illegal gathering" he will be responsible for the consequences.
I certainly sense that the opposition supporters are as determined as ever. When they go out, nightly now, to chant "God is Great" as a gesture of defiance, it is louder than ever before. So the opposition supporters are definitely absolutely up for whatever their leaders instruct them to do, but we have not yet heard firm word of what they have been called to do.
Further protests would be very concerning for the government, but also everyone's worry now is what would happen, what sort of force the government might use against the protesters. This really could be a key moment.
JONATHAN BEALE, WASHINGTON, 2000 GMT (Friday)
President Obama continues to tread a fine line in commenting on Iran - anxious not to be seen as interfering.
In an interview with CBS, the president said the world was watching the government of Iran - perhaps his strongest warning so far. But many Republicans in the US still believe that the president has been far too cautious.
A White House official said the president was pursuing a policy that advanced US interests - rather than a foreign policy that just made it feel good about what it was saying.
JONATHAN MARCUS, LONDON, 1600 GMT
The British government has pursued a very cautious public line on the events in Iran, eager to avoid courting just the sorts of comments made by Ayatollah Ali Khamenei earlier.
He launched a strongly worded attack on the diplomacy of a number of western countries, characterising them as "hungry wolves" waiting in ambush for Iran.
The reason for this characterisation is unclear, though the Iranian authorities have been especially annoyed by the BBC's new Persian Television service.
This heightened level of rhetoric is what has prompted the British government to invite the Iranians into the Foreign Office for an urgent meeting.
MARCUS GEORGE, TEHRAN, 1000 GMT
Very robust words indeed from the supreme leader. Ayatollah Khamenei said the election results are fine and there's no way that any vote rigging could have happened in this nation.
That would be treacherous, he said. He has effectively endorsed Mahmoud Ahmadinejad's landslide win. He said it just isn't possible to have vote rigging here.
In the meantime, he has told Western nations, keep your nose out of our business, these are domestic affairs you are meddling in and you are responsible for the allegations of vote rigging to begin with.
JON LEYNE, TEHRAN, 0620 GMT
The government needs to turn out as many people as possible - to show they can rally as many supporters as the opposition. So they've been putting out appeals on state media constantly, offering free transport, calling on people to turn up, not just to Friday prayers but to an "anti-riot rally", as they describe it.
From the Supreme Leader the key thing is, which way does he go - does he offer a message of conciliation, and is that followed up by conciliatory gestures, or conversely, does he go for a very hardline message which will signal a crackdown?
MAGGIE SHIELS, TECHNOLOGY REPORTER, SILLICON VALLEY, 0510 GMT
Search giant Google has ramped up work to release a tool that will translate Farsi into English and from English to Farsi.
The company told the BBC that the huge world interest in what is going on in Iran was the reason they accelerated work on the project. At the same time the world's biggest social networking site, Facebook, is providing a Persian version with help from hundreds of Persian-speaking users.
Both companies say they hope it will improve access to information
A BBC CORRESPONDENT, TEHRAN, 2115 GMT (Thursday)
The man the crowds accuse of stealing the election, President Ahmadinejad, has gone on television to try to be conciliatory.
When he said the other day that protesters were acting like angry football fans, he explained that he meant only the ones who were rioting.
In this election, he said, everyone is a winner.
But the people in the streets do not feel that they are winners. They feel that their votes have been stolen and President Ahmadinejad has treated them with contempt by announcing a victory they think is an obvious steal.
A few conciliatory words on television will not be enough to deal with their anger.
JON LEYNE, TEHRAN, 1730 GMT
The disputed election has unleashed deep emotions amongst many Iranians bitter about a government and a system that they believe fails to meet their aspirations. When they chant "death to the dictator" it is surely directed at the Supreme Leader, Ayatollah Khamenei.
Whether the opposition understand it or not, they are implicitly challenging the whole system. Members of the opposition believe Mr Ahmadinejad bribes people to support him, and busses them in to his rallies. But there is plenty of fervour in his camp as well.
Behind the scenes there is an equally bitter dispute between the Supreme Leader and former President Rafsanjani, who is backing the opposition.
While the leader may control many levers of power, Mr Rafsanjani heads the Assembly of Experts, which has the power to elect the leader, supervise him, and theoretically even to dismiss him So it is a political battle between two veterans of the Islamic Revolution, but also a titanic dispute about the whole future of Iran, whose outcome no-one can predict.
MARCUS GEORGE, TEHRAN, 1700 GMT
More than 100,000 opposition supporters took to the streets of Tehran, shouting "Mousavi, Mousavi. Give back our votes".
Marching towards Revolution Square, many were clad in black, waving black banners to mourn those killed in protests earlier this week. Others held aloft placards asking: ''Why did you kill our brothers?"
The opposition leader also attended the rally. According to eyewitness accounts, he addressed the crowds through a loud speaker.
Eyewitnesses say there is little sign of police or pro-government militia on the streets but supporters have been telling each other to stick closely together for better protection.
JIM MUIR, BAGHDAD, IRAQ, 1530 GMT
Big issues like relations with the United States and Iran's nuclear ambitions are not in the hands of the Iranian president, whoever he may be.
They are decided by Supreme Leader Ayatollah Ali Khamenei.
But it is not quite that simple. For one thing, the president can do a lot to set the tone of Iran's relations with the outside world. For another, the contest is now over the balance of power within the Islamic leadership.
Which way it tilts will have a big effect on how Iran relates to the world, as well as internally.
President Ahmadinejad did send a message of congratulation to Mr Obama on his election. But he is very hard-line and regards Iran's nuclear programme as non-negotiable.
His rival, Mir Hossein Musavi, has said he will work to improve Iran's relations with the world.
He would have to bow to the leader on issues like the nuclear one and relations with Washington. But if he does somehow prevail in the current struggle, that would mean the balance of power had shifted and the leader himself would have to adjust to that.
A BBC CORRESPONDENT, TEHRAN, 1630 GMT
The crowd is enormous. It is impossible to put any kind of estimate on the numbers because it is so spread out. It starts down in a large square, Iman Khomeini square, and is filling the streets and avenues all around.
The most you can say is that there are several hundred thousand people here. And just like Mr Mousavi asked, the great majority are wearing sombre clothes. Many are in black, especially the women, who have turned out wearing black chadors.
It is, in effect, a funeral procession for the eight people who were killed here in Tehran on Monday, and the perhaps seven or so who have been killed in other parts of the country.
But the most remarkable thing about this demonstration is the complete silence. The only sound is a certain amount of conversation. There is no shouting, no chanting - just a really dignified silence.
MARCUS GEORGE, TEHRAN, 1300 GMT
According to eyewitness reports thousands of opposition supporters have congregated in Imam Khomeini square in southern Tehran. Many are dressed in black to mourn those killed in protests earlier this week.
Supporters are telling each other to stick closely together for better protection. They say that the pro-government militia squads will be out in force at the protest.
The opposition leader, Mir Hossein Mousavi, has called for the growing number of those arrested to be released. It is reported that more senior opposition figures have been detained including Ebrahim Yazdi, a former foreign minister-turned government critic.
JON LEYNE, TEHRAN, 0500 GMT
Another day of huge demonstrations is in prospect, as the opposition calls a day of mourning for those killed in previous protests.
Opposition leader Mir Hossein Mousavi has called his followers to come out dressed in black. He has also called for the growing number of people arrested to be released.
The Iranian authorities have stepped up their attacks on foreign governments for what they have described as illegal, interfering and adventurous remarks.
A number of Western ambassadors have been summoned to the foreign ministry, including the Swiss ambassador, who represents US interests, and the British ambassador, who has now been called in at least twice.
President Ahmadinejad told a cabinet meeting the election posed a great challenge to the West's democracy.
Official media are already encouraging Iranians from across the country to attend Friday prayers, and offering transport. They will be addressed by Supreme Leader Ayatollah Khamenei.
A BBC CORRESPONDENT, TEHRAN, 2100 GMT (Wednesday)
Thursday looks like being a really important day.
The defeated candidate Mir Hossein Mousavi has called on all his supporters to go to the mosques to commemorate the deaths of the eight people who were killed here on Monday, shot down by the Basijis, the fierce paramilitary police.
It is very important for the opposition to keep people in the streets - that's the one way they can maintain pressure on the government
The question is what does the government do about it? Does it give orders to the police to shoot? Well, probably not. But nevertheless, people were shot on Monday. That's the trouble with these situations. They can get out of hand in a second.
MARCUS GEORGE, TEHRAN, 1810 GMT
How is the Iranian media reporting the ongoing crisis? The finger on Iranian state television is pointing at what it describes as the damaging effects of international media.
Some TV reports say foreign news organisations are taking advantage of the unrest, their goal to destabilise the Iranian government.
One interviewed commentator, Dr Amani, says: "These channels are openly playing the role of command headquarters for all the unrest."
Also on state television are pictures of damaged buildings, burning cars, scenes portrayed as evidence of widespread violence.
Callers into the programme give their views on events over the past few days. "I congratulate Mr Ahmadinejad for a great victory," says one. Another says: "Those protesters who caused the damage should be arrested and put on trial."
Conspicuously absent is news of Wednesday's peaceful march by members of the opposition.
With the international media restricted from reporting on the daily protests, Iranians and the outside world are now relying on network-sharing sites to get a full picture of what is happening on the streets of Tehran.
KIM GHATTAS, WASHINGTON, 1735 GMT
Is US President Barack Obama saying too little or too much about events that will have a deep impact on American foreign policy?
Writing in the the Washington Post newspaper, conservative analyst Robert Kagan argues that the Obama administration needs a quick resolution of the controversy surrounding the Iranian election so that it can get down to business and begin negotiations with Mahmoud Ahmadinejad about Iran's nuclear programme.
Mr Kagan said the US president had to deflate the opposition not encourage it.
Others believe negotiations would simply become too difficult with Mr Ahmadinejad if he continued to violently quell the protesters.
And some took issue with the American president's comments about Mir Hossein Mousavi. Mr Obama said there was little difference between the president and his rival men when it came to Iran's nuclear ambitions and its foreign policy.
But Afshin Molavi, an Iranian analyst with the liberal New American Foundation think tank here, feels that this statement was a mistake - regardless of his politics Mr Mousavi has become a symbol for Iranians seeking more freedom, argues the analyst.
In the end the best advice for the Obama administration may be to remain nimble as events on the ground could overtake previously stated policies.
JON LEYNE, TEHRAN, 1645 GMT
Once again, huge numbers of protesters are marching through central Tehran.
The government has banned foreign media from attending, but witnesses say tens of thousands of people, possibly hundreds of thousands, are there. Many are wearing black in memory of protestors killed.
The opposition leader, Mir Hossain Mousavi, has already called for a major gathering tomorrow, also in memory of those killed - all strangely reminiscent of the cycle of deaths and protests in the 1979 Islamic revolution.
The government has arrested more opposition leaders and threatened opposition bloggers but still has no clear strategy on how to respond.
JON LEYNE, TEHRAN, 1200 GMT
Iran's Revolutionary Guards have warned Iranian websites and bloggers to remove material that creates tension.
Members of the Iranian football team have gone on the field wearing armbands in opposition colours in a crucial World Cup qualifier
By intervening so directly in his latest appeal for calm after days of protests against the election results, the Supreme Leader of Iran, Ayatollah Khamenei, is reducing his political authority.
Ayatollah Khamenei usually stays above the fray and interestingly he's still not been seen in public since the election.
During the night, student dormitories in several cities were attacked by members of the basij, the government militia.
There have been more arrests of prominent opposition figures as well. But the opposition appears undeterred.
MARTIN VENNARD, WEST ASIA ANALYST, 0945 GMT
The fact that the Iranian authorities are allowing domestic media outlets to report on the opposition demonstrations shows they are far too big for the government to be able to prevent the wider public from finding out about them.
Even the government-owned newspaper, Etelat, whose director is appointed by Iran's supreme leader, carried a large front-page picture of the rally by supporters of the opposition candidate Mir Hossein Mousavi.
At least one other newspaper, as well as state and satellite TV channels, also covered both rallies.
All this, coming after the authorities attempted to cut communications, censor the internet and curb reporters underlines the view of many commentators that there are big conflicts within the government over how to handle this crisis.
A BBC CORRESPONDENT, TEHRAN, 0001 GMT
You get the impression that really what's going on here is that people are getting themselves together for what happens in a week's time when the Guardian Council, the supreme grouping of the country, will give its verdict on the election itself; whether it was false or true.
Hard to think they can possibly say President Ahmadinejad won't continue to be the president.
And then what happens?
JUSTIN WEBB, WASHINGTON, 2130 GMT (Tuesday)
In an American television interview Barack Obama made a highly significant observation: the difference between Mahmoud Ahmadinejad and Mir Hossein Mousavi in terms of their actual policies may not be as great as advertised, he said.
In other words, the United States is wary of becoming sucked into a global protest movement in favour of the challenger.
But Mr Obama's facing growing pressure here to take sides. John McCain his Republican challenger in the 2008 presidential election, urged Mr Obama to speak out against the "corrupt, fraud, sham of an election".