MOSCOW — A high court in Ukraine began Wednesday to consider Prime Minister Yulia V. Tymoshenko’s request to overturn the results of the country’s presidential election, which she narrowly lost.

While it hears her appeal, the court will temporarily suspend the official declaration of victory for Viktor F. Yanukovich, the opposition leader. The move was considered a formality, and the court did not postpone or cancel Mr. Yanukovich’s inauguration, scheduled for Feb. 25.

The court, the Higher Administrative Court in Kiev, will probably rule by the weekend on the validity of the Feb. 7 election.

Ms. Tymoshenko lost by 3.48 percentage points, according to official results announced by the Central Election Commission on Sunday.

On Saturday, Ms. Tymoshenko announced that she would not concede, and declared that Mr. Yanukovich’s campaign had stolen the election by engaging in widespread fraud.

She said that while she would challenge the election legally, she would not organize mass protests like those that occurred during the 2004 Orange Revolution, which she helped lead.

Mr. Yanukovich’s aides have described her accusations as false and desperate. European election monitors praised the election, saying that it was fair and represented an important step forward for Ukraine’s democracy. President Obama and other world leaders have already congratulated Mr. Yanukovich for his victory.

While the judicial system in Ukraine can be unpredictable, analysts have said the odds are against Ms. Tymoshenko’s overturning the election. They said she was going to court to send a message to her supporters that she would not easily give in.

She may also be seeking leverage to negotiate with Mr. Yanukovich over whether she will be able to remain prime minister. She has rebuffed his call that she resign.