Lawyers for Yukos Oil Co. lost a series of battles Friday to delay proceedings on a $3.4 billion tax claim against the giant enterprise, whose founders are being tried on fraud charges.

The Moscow Arbitration Court rejected five appeals by Yukos to postpone hearings on the Tax Ministry's claim, as well as a defense request that the judges be taken off the case for alleged bias.

However, the court also postponed a crucial ruling that lawyers said would prevent the company from appealing the claim.

The appeals followed President Vladimir Putin's statement Thursday that the government did not want Yukos to go bankrupt, a possibility its managers have raised repeatedly, saying the company does not have enough money to cover the claim if forced to pay it immediately.

Putin's statement eased investors' concerns that the state is out to destroy Yukos and sent its stock sharply higher. But many observers predicted the Tax Ministry would drive its hefty claim home to set the ground for a deal with the company's owners, led by jailed billionaires Mikhail Khodorkovsky and Platon Lebedev, on yielding control of their assets.

"I think the government's final goal is to ensure that the company will not be bankrupted, but at the same time that today's majority shareholders . . . will not have the controlling stake," Mikhail Zadornov, a member of the Russian legislature and a former finance minister, told Ekho Moskvy radio.

On Friday, as the court session dragged on, Yukos lost decision after decision -- the same results that have plagued Khodorkovsky and Lebedev, who went on trial this week and remain jailed after courts repeatedly rejected their pleas for release on bail or house arrest.

But a ruling on the central issue before the court -- the ministry's effort to overturn the same court's decision in May to cut the original tax claim by the equivalent of about $14,000 -- was put off. While the disputed amount is small, Yukos lawyers said the ruling is important because it could lead to an appeals court decision on the claim itself, which would be considered final.

Sergei Pepelyayev, a lawyer for Yukos, said the ministry apparently filed the motion to try to win a quick verdict blocking any further Yukos appeals. "We call that dirty judicial tactics," he said during a break.

An employee pumps gasoline at a Yukos station in Moscow, not far from where court proceedings were being held about the company's future.