By Paul Reynolds
World Affairs correspondent, BBC News website
Britain and Iran remain locked in diplomatic deadlock over the 15 captured British sailors and marines.
The best hope at the moment is an exchange of diplomatic notes which has taken place. There is private diplomacy as well as public comment.
The British government has accused Iran of "parading" the crew
Iran has meanwhile used two of the prisoners to make confessions on television that they entered Iranian waters illegally but also to state that they were being well treated. Iran has therefore projected itself as the injured party, one that is correct to demand an apology but also one that is treating its prisoners well.
It has also got captives to call for the US and UK to withdraw from Iraq and to stop its "intervening policies", as one of the letters from Faye Turney put it.
Britain has countered with GPS readings to show that its personnel stayed on the Iraqi side and has undertaken a diplomatic offensive, getting some help from the Security Council and more from the European Union.
The Council simply expressed its "grave concern" and generally weakened the strong message the British wanted. Perhaps memories on the Council of the invasion of Iraq (without which the naval party would not of course have been there) played a part here.
The EU did "deplore" the capture and threatened unspecified "measures" if there was no early release.
However, Britain is refusing to apologise.
The diplomatic note exchange that began on Friday with a relatively mild message from Iran through the British embassy might lead somewhere. It referred only to the need for an explanation for the "violation" and not to a specific apology. It also spoke of wanting a "guarantee" that this could not happen again.
"It will be appreciated if the esteemed embassy conveys
this note to the relevant authorities of its government and
informs this ministry of any explanation in this regard," the note said.
Britain has sent a reply. If the diplomatic track is the way out of this, the question is whether a form of words can be found to satisfy both sides. That might mean, among other things, an agreement about new arrangements along the maritime border. Iran is extremely sensitive about its borders, fearing an attack on its nuclear plants.
The problem is that nobody really knows how long the Iranians want to play it. They might, of course, not yet know themselves. If they stick to demanding an apology, it could go on for some time.
They could hold some sort of trial. That might be a way out -- a trial and an expulsion.
If they have other intentions, it could go on even longer.
The US has ruled out one earlier suggestion floated in the international media, that the 15 might be swapped for five Iranian officials held by the US in Iraq. Iran has made no such offer or demand. The suggestion is based on the fact that the five detained Iranians are said by the Americans to be Revolutionary Guards, the same organisation that took the British prisoner.
On the other hand, if the Iranians feel they have made their point and their propaganda, they might seek a way out. A long holiday there has just ended so it is possible that this will be an opportunity for the government as a whole to reflect.
Iran and Britain have differing technical accounts of the incident
But reports from Iran also indicate a level of public anger at Britain (often seen in Iran as a meddler).
BBC Monitoring reported that the semi-official news agency
Fars carried news reports on anti-British
sentiments among 60,000 Iranian youth who were in Tehran's
football stadium to attend the most famous
derby match in the capital. They chanted
"Death to Britain".
A lot will depend on the role of President Mahmoud Ahmadinejad, though in Iran's political pyramid he does not command total power. He is quoted by the Iranian news agency Irna as telling the Turkish Prime Minister Recep Tayyip Erdogan that Britain was conducting a "fabricated hue and cry" instead of apologising.
"The issue is now under judicial review due to the British government's improper approach," the president is quoted as saying.
The "H" word is even beginning to be used in the British media. For example, The Independent refers to the British sailors "seven days after they were taken hostage." The Times wrote of the "hostage crisis". The Telegraph also used the word.
The spectre haunting the British government is that of 1979, when Iranian revolutionaries, President Ahmadinejad believed to be among them, held American embassy staff for 444 days.
The president thrives on confrontation. This calls into question Britain's policy of isolating Iran. The British government is following the textbook way of responding in such a crisis but Iran does not read textbooks. It is already isolated over the nuclear issue and under UN sanctions. It has been economically boycotted by the United States since 1979.