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With Ukraine's (search) opposition and government awaiting a Supreme Court decision on disputed presidential elections, international mediators were renewing efforts Wednesday to defuse a tense situation that has provoked massive protests.

But the hurdles were high after the last internationally brokered negotiations broke down over accusations by the opposition that the government was trying to consolidate its flagging authority by dragging out talks.

Opposition candidate Viktor Yushchenko (search) is pushing to be declared the outright winner — or to get a fast revote to capitalize on the momentum generated by a 10-day street protest that has paralyzed Kiev and government business.

European Union foreign policy chief Javier Solana arrived in Kiev late Tuesday and was to be followed Wednesday by Polish President Aleksander Kwasniewski (search) and the secretary general of the Organization for Security and Cooperation in Europe, Jan Kubis. The speaker of the Russian parliament, Boris Gryzlov, and Lithuanian President Valdas Adamkus were also expected to participate.

On Friday, mediators helped arrange talks that brought together Prime Minister Viktor Yanukovych, the Kremlin-backed candidate declared the official winner of the Nov. 21 presidential runoff, and Yushchenko, the Western-leaning opposition candidate who has accused the government of stealing the election through rampant fraud.

The two campaigns agreed to set up a working group to grope for a compromise, but the opposition pulled out of those talks Tuesday.

A revote was likely to be high on the agenda of Wednesday's meetings with the international mediators. Outgoing President Leonid Kuchma endorsed the idea Monday, but the government appeared to be maneuvering for a way to keep Yushchenko from taking part.

Yanukovych suggested Tuesday that he could agree to Kuchma's proposal for a new election — but that both he and Yushchenko should bow out if one is held.

"If this election brings a split in the country ... I'm ready to drop my bid along with him," Yanukovych said.

Yushchenko ignored the proposal. He also rebuffed the offer of the prime minister's post under a Yanukovych presidency, saying it fell far short of a solution to Ukraine's crisis.

"The election was rigged," he said. "People are asking whether this country has a political elite capable of upholding a fair vote."

Yushchenko has led the opposition for years and was long seen as its candidate in a country where millions are yearning for change after Kuchma's 10-year rule. His name has become the protesters' rallying cry and is chanted around the clock in the opposition's giant tent camp on Kiev's main street.

By contrast, Kuchma anointed Yanukovych as his favored successor just last spring, hoping his prominence as prime minister would attract votes.

Solana, who met with Kuchma on Tuesday night, voiced hope the two sides could be brought back to the table. "I'm sure that with the good will of everybody we will see the progress in the coming days," Solana told reporters upon arrival.

Both campaigns are pinning their hopes on the Supreme Court, which was convening for a third day Wednesday to consider Yushchenko's appeal of the vote. It remains unclear when a ruling will come.

The political crisis stoked fears of Ukraine's breakup. Yushchenko draws his support from the Ukrainian-speaking west and the capital, while Yanukovych's base is the Russian-speaking, industrialized east. The risk of a split, however, seemed to wane Tuesday after Kuchma had stressed the need for unity and the Ukrainian security agency launched a probe against regional governors who called for autonomy.

The conflicting parties also clashed Tuesday in parliament, with pro-government lawmakers blocking an opposition attempt to vote no-confidence in Yanukovych's Cabinet and trying to annul Saturday's nonbinding decision declaring the election invalid. After throngs of opposition supporters tried to storm into parliament, parliament speaker Volodymyr Lytvyn called a break in the session until Wednesday.

In the Supreme Court, the opposition presented its allegations of fraud in the runoff and demanded to name Yushchenko the winner based on his narrow edge in the election's first round on Oct. 31.

The West has refused to recognize the runoff results, while Russia — which still has considerable influence over Ukraine — congratulated Yanukovych and complained of Western meddling.