According to Rosneft president Sergei Bogdanchikov on Thursday, nearly $5 billion in tax debts the Russian government says Yuganskneftegaz owes would be shifted to Yukos' shareholders.
Bogdanchikov told a news conference in the eastern city of Yuzhno Sakhalinsk that "as a result of a specific policy, which Yukos conducted in relation to Yuganskneftegaz, the company has suffered damages ... and so, we must now turn back this [debt] to the shareholders of Yukos, which mismanaged the company".
Rosneft acquired Yuganskneftegaz following a disputed auction in December, which the government conducted to pay off a portion of what it said was $23 billion in back tax claims owed by Yukos.
Yuganskneftegaz was Yukos' largest production unit.
The Group Menatep holding company, which was created by Yukos' jailed former chief executive officer Mikhail Khodorkovsky, controls some 60% of Yukos' shares.
Group Menatep says the auction of Yuganskneftegaz was illegal and has threatened to sue anyone involved in its sale.
Yukos owner Khodorkovsky (L) and
Lebedev are the main shareholders
Tim Osbourne, a director at Menatep Group, said it was "totally ludicrous" that Rosneft should seek to redirect the tax claims against the holding company.
"Even as a matter for Russian law ... you buy the company you buy. They knew about the tax claims against Yuganskneftegaz," Osbourne said. "Now they are reneging on the debt. I think it's a farce."
Earlier on Thursday, Interfax reported Bogdanchikov as saying that Rosneft was ready to participate in a planned oil pipeline from Siberia to a port on Russia's Pacific coast.
The pipeline, which is expected to cost between $11 billion and $16 billion will have a capacity of 80 million tons per year and will supply the oil-hungry economies of Japan and China.
Bogdanchikov said Rosneft's plans to produce 78 million tons of oil in 2005.
Meanwhile, a Moscow court refused to overturn the arrest of a Yukos lawyer charged with asset-stripping.
Svetlana Bakhmina was detained for questioning by prosecutors on 8 December. Moscow's Basmanny court has extended her custody until 2 May.
Bakhmina's lawyer Olga Kozyreva argued that her client had been illegally detained while only a suspect in the case, Interfax reported.
"Bakhmina was just a suspect, not a defendant, when she was taken into custody," Kozyreva said.
Most of Yukos' top management currently works from abroad, having fled Russia for fear of prosecution.