Jubilant opposition supporters in Ukraine have gathered in celebration in the central square of the capital, Kiev, after exit polls gave their leader, Viktor Yushchenko, a formidable lead over the pro-Russian candidate, Prime Minister Viktor Yanukovich.
One exit poll said that Mr Yushchenko had scored 56.5% to 41.3% for Mr Yanukovich, while another put the opposition leader's share of the vote at 58.1% to Mr Yanukovich's 38.4%.
Mr Yanukovich vowed to fight in opposition if he fails to win the presidential race and told reporters he would create a strong opposition if defeated.
The presidential ballot was a repeat of the November election which was annulled by the Ukrainian Supreme Court amid allegations of fraud and vote-rigging.
Couting of votes has got underway across Ukraine, and preliminary results from the election are expected tomorrow morning.
Earlier today, both camps were on the lookout for potential fraud and traded accusations over alleged infractions.
Opposition officials in Donetsk charged that thousands of people have been illegally added to the voting lists in an area that tends to support Mr Yanukovich.
In Crimea, Mr Yushchenko's campaign said there were 'too many violations to list' while Yanukovich backers charged their opponents with using illegal tactics.
