The Ukrainian opposition leader Mr Viktor Yushchenko has tonight urged tens of thousands of supporters to defy authorities and continue their protest in central Kiev over the presidential election which they believe was fraudulent.
More than 100,000 Ukrainians poured into the streets of the capital to support the West-leaning Mr Yushchenko, who says he was robbed in the vote by supporters of Prime Minister Mr Viktor
Yanukovich.
With political tension running high after yesterday's run-off ballot, Ukraine's security bodies reacted sharply, saying unlawful conduct would be put down "quickly and firmly".
The prosecutor general, the interior ministry and the security services issued the statement as 100,000 protesters, denouncing an official count showing Ukraine's prime minister as winner of a presidential election, occupied Kiev's main square.
"We appeal to the organisers of mass protests to assume responsibility for their possible consequences," the statement said.
"We want to assure everyone that in the event of any threat to constitutional order, and the security of our citizens, we are prepared to put an end quickly and firmly to any lawlessness."
Protesters have avoided all violence but blocked traffic on the capital's principal thoroughfare.
Liberal opposition candidate Viktor Yushchenko, addressing the crowd, said he had no confidence in election officials organising the count giving Prime Minister Viktor Yanukovich an unassailable lead. He called for parliament to be summoned.
Four cities in Ukraine's western heartland have said they will only recognise Yushchenko as legally elected president.
The claim that the election was rigged was largely substantiated by international observers. The Organisation for Security and Co-operation in Europe (OSCE) and other Western election observers said the general election did not meet international standards for democracy.
Assessments of the outcome are contradictory, with most exit polls yesterday showing challenger Mr Viktor Yushchenko with 54 per cent of the vote.
But the Ukraine's central electoral commission say that with 99 per cent of votes counted today, Prime Minister Viktor Yanukovich - the establishment candidate backed by Moscow - has an almost unassailable three percentage points lead.
Kiev city council called on parliament not to recognise the result. The move put the capital on a growing list of major cities rebelling against election commission results. The cities of Lviv, Ternopil and Ivano-Frankivsk announced they recognised Mr Yushchenko as the legally elected president.
International monitors said accepted standards for voting had not been met after a first round of voting three weeks ago proved inconclusive.
"The second round [of voting] did not meet a considerable number of [international] commitments for democratic elections," Mr Bruce George, head of an OSCE mission, said.
"The deficiencies have not been addressed. The abuse of state resources in favour of the Prime Minister continued, as well as an overwhelming media bias in his favour," Mr George said.
The mission reported cases of public sector employees and students being pressured to support the incumbent and a "lack of will" on the part of authorities and the election commission to conduct "a genuine democratic election process".
Mr Yushchenko held a rally calling for supporters of his pro-Western, liberal policies to engage in a campaign of civil disobedience late last night.
"Remain where you are," he told an estimated 100,000 demonstrators who answered his call, spilling out of Independence Square and down Khreshchatyk, Kiev's tree-lined main thoroughfare.
"From all parts of Ukraine, on carts, cars, planes and trains tens of thousands of people are on their way here. Our action is only beginning," Mr Yushchenko said.
"The will of the people cannot be broken. The voice of the voter is sacred. We won. The Ukrainian people have won. . . . A coup d'etat is already under way in Ukraine. . . . We won. Full stop."
Mr Yushchenko called for cancellation of results declared in districts of eastern Ukraine, Mr Yanukovich's stronghold, where he said turnout had exceeded the number of voters on lists. He also demanded an emergency session of parliament and appealed to the West to take note.
He said outgoing President Leonid Kuchma was implicated in fraud by refusing to sign a bill passed by parliament last week aimed at halting fraudulent voting with absentee ballots.
Agencies