He told supporters to stay in the streets until incumbent President Leonid Kuchma has sacked the government and replaced the election commission that presided over the vote that has now been ruled dishonest.
Lawmakers today met to discuss potential changes to the makeup of the Central Election Committee.
Opposition Deputy Yuriy Klyuchkovskiy said that changing the electoral body is essential.
"The present composition of the Central Election Commission took part in deeds that were the opposite [of the honest conduct] they were supposed to engage in," Klyuchkovskiy said. "In these circumstances, it seems to me that the president, under the constitution, is simply obliged to remove the credentials of the [election commission] members and propose new members according to the laws governing the [commission] in consultation with the various factions of parliament."
Further Opposition Demands
The opposition also hopes to press through a resolution approved on 1 December to fire Yanukovych and his government.
Kuchma has not accepted the nonbinding measure to remove Yanukovych.
Ivan Lozowy, a political commentator and head of the independent Kyiv-based Institute for Statehood and Democracy, said the makeup of both the government and the election commission must change in order to ensure the next round is fair.
"The re-run of the second round can only be more or less fair, transparent, and honest if there are significant changes to those responsible for the conduct of those elections. That is, first and foremost, the members of the CEC, members of regional election administrations, and the minister of internal affairs -- who, even now, has not launched any criminal investigation into the massive electoral fraud which the Supreme Court has ruled took place."
Yanukovich has indicated he will stand in the 26 December runoff.
Some opposition members have speculated that Yanukovych might ultimately withdraw. If that happens, Yushchenko would need only to win the support of a majority of those who turn up to vote.
Achieving those numbers could be relatively easy, unless there is a large-scale boycott of the vote.
A boycott could lend strength to separatist leanings in eastern and southern Ukraine, where some politicians have reportedly proposed the formation an autonomous entity opposed to Yushchenko.
One senior opposition member, parliamentary deputy Petro Poroshenko, said a Yushchenko victory will bring the country together, not divide it.
"We will stop the attempts to split the territorial integrity of the country," Poroshenko said. "I am sure that the east and the west, the south and the north, will vote for Yushchenko. I am sure that we can expect a united Ukraine to bring an upsurge in social development and the economy, and an end to the political crisis. We have shown that the constitution and the law have become a reality in Ukraine."
International mediators were due to hold fresh talks with both sides in Kyiv today. Polish President Aleksander Kwasniewski and his Lithuanian counterpart, Valdas Adamkus -- who were both expected to participate -- today canceled their trips.
Recent related stories:
"Ukraine's Parliament Meets To Prepare For Repeat Vote"
"Ukraine: Ethnic Relations Good, But Some Fear Russian Manipulation"
"Frequently Asked Questions" about the Ukrainian crisis
"Politicians To Watch" as events unfold
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