MOSCOW (AFP) - The billionaire Russian owner of Chelsea football club, Roman Abramovich, faced accusations of acting in the Kremlin's interests by calling off a mega merger between his Sibneft firm and the struggling Yukos oil giant.

Yukos, whose main shareholder Mikhail Khodorkovsky is behind bars, was plunged into confusion after Sibneft on Friday dropped a bombshell by breaking off a merger creating the world's fourth-biggest oil company at the last moment.

The Moscow press pointed the finger at 37-year-old Abramovich for the sudden demise of the deal, saying he had tried to force Yukos to hand over management control of the combined group to his Sibneft firm.

"When Yukos didn't accept the ultimatum, Sibneft was obliged to announce the suspension of the merger," the ****Vedomosti**** business daily said.

Newspapers suggested that Abramovich had not acted of his own initiative but instead agreed his move with President Vladimir Putin whom he reportedly met recently.

Exiled Russian tycoon Boris Berezovsky, who says he was forced to sell his 50-percent share in Sibneft to Abramovich under duress in 2000, said he was convinced his former protege was acting in concert with the Kremlin.

"This was an attempt to put a company under control of people who are loyal to Putin, and no one has ever hidden the fact that Abramovich is loyal to Putin," he told AFP by telephone from London.

"Everything became clear when they made the indecent proposal of putting things under Sibneft's control while Khodorkovsky is sitting in jail," Berezovsky added.

Yukos, the largest oil producer in Russia, has been under legal attack over the past six months from prosecutors in a struggle that many see as a bid to quash the political ambitions of Khodorkovsky, Russia's richest man.

Khodorkovsky was arrested and charged with fraud and tax evasion on October 25. According to media here, Abramovich began to have doubts about the wisdom of tying his fortunes to a company facing the Kremlin's wrath.

The deal, first unveiled in April and virtually complete, gave him 26 percent of Yukos.

"The shareholders (of Sibneft) were threatened with losing their business because of the Yukos affair. To save it, Sibneft was forced to go turn to the Kremlin for advice," Vedomosti said.

The ****Kommersant**** business daily commented that Abramovich could now try to mount a takeover of Yukos despite its much bigger size, which suited the wishes of the Russian authorities as they were keen to have the powerful oil group taken away from Khodorkovsky.

"It's extremely likely that Yukos in one form or another will come under the control of Roman Abramovich," it said.

A source in the Russian presidential administration applauded the behavior of the tycoon, who has come under domestic criticism for selling off most of his Russian assets and splurging hundreds of millions of dollars on Chelsea.

"He is making the right choice politically and after the break-up with Yukos the authorities won't have any problems with him," ****Vedomosti**** quoted an unnamed Kremlin official as saying.