Thousands of Ukrainians are continuing their protests
Ukraine is gripped by a complex political crisis as hundreds of thousands of people continue to demonstrate over the hotly disputed presidential election.
Allegations of vote-rigging have led to calls for a fresh poll.
The BBC News website's Stephen Mulvey, an expert on the region, is in Kiev and is closely following developments.
If you have any questions about the situation in Ukraine and what might happen next, you can send your questions to him using this form.
Here are some of your questions so far:
THREAT TO UNITY
Marc Wallace, Chicago, Illinois, US: I have read about some referendums that would split the country. Do you see any threat to Ukraine's unity?
Stephen's answer: I talked to the head of the Donetsk regional council, Boris Kolesnikov, on Friday. He is widely regarded in Kiev as a dangerous separatist. However, in his conversation with me and another BBC correspondent, he said he was firmly against separatism or any measures that would split the country. He is planning a referendum in January in which the people of the Donetsk region will vote on whether Ukraine should become a federation. The idea is to give the regions more power, and to trim the powers of the centre. Donetsk, which has 10% of Ukraine's population and contributes 20% of its GDP, would give less money to the centre. But Mr Kolesnikov argued that federalisation would strengthen Ukraine, in fact that it would "save" the country (without specifying from what). He pointed out that the election had revealed deep divisions, which he said ought not to be ignored. I am unsure what danger, if any, such a referendum holds for Ukraine's unity. It is certainly an issue that raises strong passions. But Donetsk cannot vote for federalisation by itself. To become law, a proposal on federalisation would need to be adopted by the Ukrainian parliament and by a national referendum, and this will not happen.
Alex, Moscow, Russia: Do you think current events in Ukraine will encourage people to take to the streets in Belarus and/or other countries in the region?
Stephen's answer: I find this a very difficult question to answer. I think it is clear that the events in Georgia last year, and in Serbia before that, have had some influence on the protesters in Kiev because they showed what could be achieved. However, each country is different. It may be that there are insufficient numbers of opposition supporters for the same to happen in Belarus and Russia, and no opposition leaders with mass appeal. In Russia, in particular, the government may enjoy greater legitimacy. The state apparatus may also be more resilient. Also, bear in mind that it is not only the opposition in these countries that will be looking at this phenomenon and wondering how to apply it to their situation. The governments too will be developing strategies to tackle it.
Colin Jackson, Leigh-on-Sea, England: What do the parties in Ukraine represent? Are they right-wing, left-wing, religious, ethnic or what?
Stephen's answer: One of the paradoxes of this election is that the election platforms of the two main candidates are not hugely different. Neither is left-wing, and religion does not come into it. In practice, Mr Yushchenko has the support of most of the Ukrainian-speaking part of the population, and Mr Yanukovych has the support of most of the Russian-speaking part of the population, at least in the towns and cities of the east and south, but I do not think many people would describe this an ethnic divide. It is more of a cultural issue. In so far as policy issues have stirred voters, Mr Yushchenko's desire for a rapid drive towards integration with the West has alienated some in the south and east who fear it would spoil relations with Russia, and Mr Yanukovych's proposal to make Russian a second official language and to introduce the possibility of dual citizenship (Ukrainian and Russian) has alienated voters in nationalist western regions. But personal issues have also entered into the race: Mr Yushchenko's American wife, Mr Yanukovych's biography (including two jail terms), and the ties between Mr Yanukovych and Leonid Kuchma, the outgoing president, have all had an effect.
Ivan Safonov, Methuen, Massachusetts, US: What are the chances for Ukraine to join the EU in the near future? If a pro-Western president is chosen who is promising the possibility of joining the EU but fails to attract help from the West while at the same time breaking the relationship with Russia, wouldn't that hurt Ukraine much more?
Stephen's answer: Viktor Yushchenko says he would like to start membership talks with the European Union and Nato within five years, if he becomes president. However, this is probably over-optimistic. A few years ago the EU enlargement commissioner, Guenter Verheugen, said Ukraine was as close to joining the EU as Mexico was to joining the US. Mr Yushchenko says he would not break the relationship with Russia. He says Russia is bound to remain a key trading partner, and claims that trade with Russia grew dramatically during his two-year premiership in the 1990s. The Economist has suggested that Mr Yushchenko, a liberal, might prove more accommodating to Russian business interests than Mr Yanukovych, who has close ties to some of Ukraine's home-grown oligarchs.
Giles Adcock, Valencia, Spain: Are the Ukrainian people generally excited at the prospect of future membership of the EU, or does the majority want closer ties and a stronger union with Russia?
Stephen's answer: It is hard to tell what the majority want. There are undoubtedly many who are hoping, ultimately, to join the EU, and many who regard the West with distrust. Some people make the point that they do not want to be anyone's puppet, neither Russia's nor Europe's. It is Ukraine's clearly stated policy to seek EU membership and to integrate as far as possible with Euro-Atlantic security structures, namely NATO. This policy was originally designed partly to shield Ukraine from any "imperial" ambitions that Russia may have in the region, but was not intended to prevent a close and constructive relationship with Moscow.
Mike, Vancouver, Canada: We hear that Ukraine is split geographically, what kind of minority political support does each of these two candidates receive in the other's power base?
Stephen's answer: The nine regions in the south-east where a majority voted for Viktor Yanukovych, according to the official results, have a combined population of about 23 million. The total population of Ukraine is 48.5 million. These figures come from the census of 2001. I have no hard data on the minority political support each candidate has in the other's power base. The election results, as published by the Central Election Commission, suggest that in some eastern regions support for Mr. Yushchenko is very low indeed, and equally that support for Mr. Yanukovych in the westernmost regions is minimal. It is possible that ballot stuffing has exaggerated this lack of support for the "other" candidate in some cases, but I have no doubt that it exists in reality.
ZoŽ Young, London: How much and what kind of support has Yushchenko's campaign received from the US, and how does this compare with Russia's support for Yanukovych's campaign?
Stephen's answer: The US reacted very strongly to the evidence of falsification, once election monitors had published their report, but had not openly endorsed Mr Yushchenko's candidacy. The Russian President, Vladimir Putin, by contrast, wished Mr Yanukovych luck, and appeared with him in public during the election campaign. This may well have alienated some Ukrainian voters who were undecided who to vote for.
Giovanni Munoz, Rome, Italy: Do people know about the fact that Mr Yanukovych, was convicted several years ago in Donetsk? Under Ukrainian law why does that fact not prevent him from becoming president?
Stephen's answer: He says he was wrongly convicted, but one of the reasons people often give for voting for Mr Yushchenko is that they felt it was not right for someone who was once jailed for assault to be their president. Since then a court has wiped his criminal record clean, accepting his claim to have been wrongly convicted.
Stefan, Odessa, Ukraine: Why is the supreme court taking so long to come to a decision?
Stephen's answer: The sessions of the court are broadcast live on television. The judges are hearing oral evidence, and have been handed thousands of pages of documents. I have not heard anyone argue that there is anything suspicious in the judge's failure to deliver a quick ruling. By Friday the court was already hearing closing arguments.
Tom Harrington, Gilford, New Hampshire, US: I've heard it said that there are Russian troops in Kiev. Is there any evidence of this?
Stephen's answer: I have seen no evidence of Russian troops in Kiev. I have heard reports of Russian troops in Odessa, but I have not been there, have not seen them, and I am generally sceptical. I have not even seen any Ukrainian soldiers in Kiev, and even police have been practically invisible in the areas where the main demonstrations are occurring, at least since I arrived on Saturday. Riot police guarding the presidential administration are protected by three well-organised rows of protesters, to prevent any possible hostile action against them by provocateurs or drunks. Occasionally the protesters turn their large television screen around to face the police so that they can see what is happening elsewhere in Kiev and in the country. One place in Ukraine where there have been, and always are lots of Russian servicemen is Sevastopol, Crimea. This is the main base of the Russian Black Sea Fleet.
Andrey, Lisichansk, Ukraine: What is the probability of new elections without the current candidates? How would Serhiy Tihipko, the ex-Chairman of the National Bank, and Socialist leader, Oleksandr Moroz ballot in the new elections?
Stephen's answer: Some people hold the view that if the election is held again from scratch, as President Leonid Kuchma wants, then none of the candidates who stood in the first election are eligible to stand. This is not true. It was indeed a provision that existed in an earlier election law, but it is not in the current election law. So, if there is a new election, Viktor Yushchenko will run again. However, Mr Yushchenko is not in favour of a new election. He will not willingly settle for anything other than a re-run of the second round of the election that has just taken place. More than one person has suggested to me that if Serhiy Tihipko had been the pro-government candidate, rather than Viktor Yanukovych, the election would have been much more evenly balanced. He is an intelligent, 44-year-old, relatively photogenic politician, who could have a big future in Ukrainian politics. Unlike Mr Yanukovych, he has never spent time in jail. The Socialist leader, Oleksandr Moroz, did not fare well in this election, but that may not prevent him running again.
IMPACT ON THE REGION
Andrew, Richmond, US: What sort of implications could such a victory for the pro-West candidate have for other governments in the former Soviet Union? And what effects will this have on Russia's own political and foreign policies?
Stephen's answer: There is no doubt that Ukraine's experience is being watched closely in neighbouring states and in the Caucasus. In fact some pro-democracy activists from Belarus came to Kiev to pass on their experience to the Ukrainian student action movement, Pora. Everyone here also recognises the similarity between events in Ukraine and those in Georgia a year ago - whether they approve of them or not. And on Thursday Ukrainian opposition leader, Yulia Tymoshenko, said Ukraine would "export its revolution" to Russia. Whether this is possible or not, is another matter. Russia has been keen to promote umbrella organisations grouping together the states of the former Soviet Union, for example the Commonwealth of Independent States. But these grand projects have achieved very little, and have not in fact provided Russia with an effective mechanism to project its power abroad. During his election campaign Viktor Yushchenko made clear that he saw Russia as a major trading partner, and pointed out that trade with Russia had risen sharply during his period as prime minister. He said he envisaged relations with Russia developing further in this way - through shared economic interests rather than ambitious political declarations.
Dwight Stagner, Atlanta, Georgia, US: What evidence is there of widespread voter fraud? And is violence likely in this confrontation?
Stephen's answer: A considerable amount of evidence was cited by the OSCE observers. I do not currently think that violence is likely, but it cannot be ruled out as a possibility in the longer term.
Andrey, Russia: What is your personal opinion as an outsider: are Ukrainians like Russians?
Stephen's answer: I do not think Ukrainians are like Russians. In many countries, national consciousness began to emerge in the 19th Century, and this is true of Ukraine too. The Soviet Union acknowledged the difference between Ukrainians and Russians by recording some citizens as Russians and some as Ukrainians in their official documents. If most of the citizens of Ivano-Frankivsk identify themselves as Ukrainian, there is no ethnologist or historian who can tell them that they are wrong.
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