Italy's energy giants Eni and Enel have won the latest auction of assets from bankrupt Russian oil firm Yukos.
Yukos' assets are continuing to be sold off
Their jointly owned unit, Enineftegas, has paid 151.5bn roubles ($5.8bn; £2.9bn) for Yukos' gas production firms Arcticgas and Urengoil.
The winning bid trumped rival offers, including one from Rosneft, Russia's state-controlled oil firm.
More Yukos assets will be auctioned in May. The firm went bankrupt last year after massive back tax demands.
Enineftegas' winning bid also secured it Yukos' 20% stake in Gazprom Neft, the oil-producing arm of Russia's state-controlled gas company Gazprom.
However, Gazprom confirmed it had signed an agreement with Enineftegas under which it had the option to buy the stake at any time during the next three years.
Yukos, once Russia's largest oil company, was declared bankrupt in August last year after a three-year battle against tax avoidance charges.
It eventually collapsed after it could not pay back taxes totalling $27bn.
Most commentators claim the action against Yukos was politically motivated, and punishment by the Kremlin for the political aspirations of Yukos' former boss, Mikhail Khodorkovsky.
Mr Khodorkovsky, once the richest man in Russia, had started to fund political parties opposed to President Vladimir Putin.
The businessman now remains in prison after being jailed in 2005 on tax avoidance charges.
Since then, most of Yukos' operations have fallen back into the hands of state-controlled Russian companies, most notably Rosneft, following the series of ongoing compulsory auctions.