KIEV, Ukraine – Losing presidential candidate Viktor Yanukovich appealed the results of last month’s election to Ukraine’s Supreme Court, arguing that the election should be declared invalid because of massive fraud, a court spokeswoman said yesterday.

Preliminary results from the December 26 election show opposition candidate Viktor Yushchenko winning a sound victory.

Mr. Yanukovich’s campaign manager, Taras Chornovil, said yesterday’s filing was just an “intermediate” appeal, and the main challenge will be submitted only after the Central Election Commission announces final results.

Mr. Yanukovich will ask the court to declare that it is “impossible to establish the result of the election” due to massive fraud, Mr. Chornovil said.

The appeal would be identical to the one Mr. Yushchenko used in challenging the November 21 presidential runoff, in which Mr. Yanukovich claimed victory, he said.

That runoff triggered the so-called Orange Revolution on Kiev’s streets, with protests that lasted 17 days and culminated in the Supreme Court agreeing with Mr. Yushchenko that fraud made it impossible to determine a winner in the November 21 vote.

The court then stripped Mr. Yanukovich of his victory and ordered the December 26 revote.

Mr. Yanukovich insists he remains the legitimately elected president and has vowed to fight the results of the December 26 revote. However, last week, the Central Election Commission rejected his appeal, saying he failed to prove massive fraud. International observers said that they saw no evidence of the mass vote-rigging that marred the November 21 voting.

The commission was ready to announce the final results, but election law prohibits them from declaring a president-elect while appeals are pending with the commission, press secretary Zoya Sharikova said. Mr. Yanukovich’s campaign files new appeals every day, she said.

Mr. Yanukovich, whose resignation from his post as prime minister was formally accepted yesterday, has said he holds little hope that the Supreme Court will rule in his favor, but he vowed to carry on the fight.

“The Supreme Court a long time ago turned into an organ that just takes politically oriented decisions,” Mr. Chornovil said.

Court spokeswoman Lianna Shlyaposhnikova said a three-judge panel will consider Mr. Yanukovich’s appeal today. The court already has rejected other minor appeals, but this is the first to address the election in its entirety, asking that the vote in the country’s 225 districts be invalidated.

Mr. Yushchenko, who is vacationing in the western Carpathian mountains with Mikhail Saakashvili, the president of Georgia, has expressed confidence that his victory will stand. Mr. Saakashvili, who also rose to power after massive demonstrations, has become one of Mr. Yushchenko’s strongest foreign allies.

Mr. Yanukovich’s resignation triggered the dissolution of Ukraine’s entire 20-member Cabinet, the Interfax news agency reported. President Kuchma has 60 days to appoint a new government.