Commission head Serhiy Kivalov told reporters that Yanukovych has won 49.46 percent of the vote to 46.61 percent for liberal opposition challenger Viktor Yushchenko.
"The Central Election Commission declares that Viktor Fyodorovych Yanukovych, born in 1950, the prime minister of Ukraine, is elected Ukrainian president," Kivalov said.
Yushchenko's supporters and Western observers say that the official count is fraudulent. Outgoing President Leonid Kuchma has called for negotiations.
Yushchenko's supporters are readily recognized by the vivid orange campaign colors they wear and the determination they show in the snow-covered streets of Kyiv.
They were already out early today, their numbers building. More than 2,000 had spent the cold night in tents.Fears Of Violence
Late yesterday, riot police several men deep confronted chanting protesters in front of President Kuchma's office.
The protesters moved on after Kuchma called for negotiations to resolve the dispute. Although Kuchma called for talks, he also criticized the protests as "a political farce."
Yushchenko aide Yulia Tymoshenko said the Yushchenko backers will respond to Kuchma's proposals today at a rally in Kyiv's Independence Square.
The confrontation between Kuchma's government, which backs Yanukovych, and Yushchenko's forces developed into high drama yesterday.
Before an emergency session of parliament, Yushchenko called for a repudiation of the official count.
"I hope that in the parliament, we will find deputies, 226 deputies, who will raise their hands and say that what the Central Election Commission did and what its local branches did, was a betrayal of their oath of office," Yushchenko said.
But the prime minister's allies boycotted the session and the speaker ordered the session closed. Yushchenko then took the oath of office, symbolically declaring himself president of Ukraine.
"I, Viktor Yushchenko, having been elected president by the will of the Ukrainian people, assuming this high post, solemnly pledge allegiance to Ukraine and swear to protect the well-being of my homeland and the Ukrainian people," Yushchenko said.
City council officials in three cities in western Ukraine have recognized Yushchenko as president. He says he will bring Ukraine closer to the EU and NATO. Much of eastern Ukraine, where there are many Russian speakers, backs Yanukovych and his policy of bringing Ukraine closer to Moscow.East-West Divide
The election dispute has demonstrated deep divisions not only between the western and eastern regions of Ukraine but also between East and West internationally.
Jan Peter Balkenende, the Dutch prime minister whose country holds the rotating presidency of the European Union, telephoned Kuchma to express what he called "serious concerns" about the election. Western election observers had reported inflation of voting lists on election day, multiple voting, and the use of state resources in support of Yanukovych, among other abuses.
Kuchma's office issued a statement saying that he had spoken with Balkenende. The statement warned that political issues should not be resolved in the streets.
There were signs that Ukrainian law enforcement and military officials were unwilling to use force against the demonstrators. Yushchenko's backers urged restraint both by their own demonstrators and by government police.
Roman Search, a member of Viktor Yushchenko's Our Ukraine coalition, at yesterday's session.
"We call on all law enforcement forces, on all military personnel not to carry out criminal orders and finally join the people, keep their oath of allegiance to the Ukrainian people and to the Ukrainian Constitution and recognize the sole legitimate president of Ukraine, Viktor Yushchenko," Search said.
Yanukovych has charged Yushchenko's supporters with seeking to seize power in the country illegally.
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