Yukos had maintained ABN Amro, BNP Paribas, JP Morgan Chase Bank, Calyon, and Dresdner Kleinwort Wasserstein were part of a consortium of lenders behind a probable bid for Yugansk, which was auctioned off by Russian authorities in December.

But Reuters today reports Yukos dropping its claims against those banks, though not dismissing its complaint against Deutsche Bank which it believed to be the leader of the consortium that was expected to finance a bid by Gazpromneft, a former unit of Russian gas monopoly Gazprom.

Gazpromneft did not enter a bid, but Yukos lawyers have argued that its presence at the auction and a US$1.2 billion participation fee it paid violated a US court order demanding it not take part in the auction.

"Yukos will continue to pursue damages against parties that participated in the illegal auction of Yuganskneftegaz stock," the company said in a statement.

The Russian government auctioned off Yugansk for US$9.4 billion to recoup part of the US$27.5 billion tax bill it said Yukos owed, though Yukos disputes the tax bill and says it is the victim of a Kremlin-orchestrated campaign against its now jailed former owner Mikhail Khodorkovsky.

Yugansk was bought by a previously unknown entity, Baikal Finance, which was in turn bought by state-controlled oil company Rosneft.