If as widely expected Gazprom wins the auction on Sunday, legal action to seize its gas exports "is one of the alternatives," a US lawyer acting for the shareholders' holding company, Group Menatep, told journalists in Moscow.
"The defendant can be the Russian government, the tax ministry, Gazprom, or any company that will facilitate the auction," Sanford Saunders, from Washington law firm Greenberg Traurig, added.
The lawyers said they wanted to attend the auction of 76.79% of Yuganskneftegaz, the main Yukos subsidiary that produces 60% of its oil.
"We want to see the people who we will see in court in other places in the world in the near future," said Saunders.
However, the Interfax news agency later reported that the Menatep legal team had been barred from the sale.
Apart from Gazprom's oil unit Gazpromneft, three other companies have been registered for the auction.
Some bidders are said to be
fronts for Gazprom
Saunders said he did not know the identity of the other bidders, but suggested that they could be a "front" for Gazprom.
"You'll have to peel the onion to find the true player," he said.
The lawyer did not exclude suing Germany's Deutsche Bank, which is an adviser for Gazprom and could, according to him, have helped the gas giant pay the $1.77 billion deposit to take part in the auction.