After the cancellation of the South Stream natural gas pipeline last December due to the EU’s blockage of the project, Russia announced an alternative project called the Turkish Stream which will hit the shore on the European side of Turkey near Kıyıköy.

Saudi Arabia has signed a commitment to invest up to $10 billion in Russia, the Russian Direct Investment Fund said Monday.

Oil prices suffered their biggest selloff in five months on Monday, falling as much as 8 percent as Greece's rejection of debt bailout terms and China's stock market woes set off a deepening spiral of losses.

Ukraine expects to store enough natural gas for next winter despite cutting off imports from Russia and Russian flows crossing the country destined for Europe will not be disrupted, Energy Minister Volodymyr Demchyshyn said on Thursday.

Russia has been hit by lower oil prices and by Western sanctions over its role in the Ukraine crisis. Its rouble currency fell sharply against the dollar in 2014 and has yet to recover.

Construction has begun on the Chinese section of the Russia-China Gas Pipeline, according to China National Petroleum Corp.

Russia’s top investigative body, the federal Investigative Committee, said on its website Tuesday that it wants to question Mr. Khodorkovsky about the murder of Vladimir Petukhov, the mayor of the Siberian city of Nefteyugansk, where Yukos had its biggest oil-production unit.

The European Union would find it difficult to reduce its reliance on natural gas imports from Russia, according to industry experts.

New corridors along the Nord Stream natural gas pipeline through the Baltic Sea to European markets should be in service by 2019, Russia's Gazprom said.

States are attempting to get their hands on long-term gas supply contracts with the Russian natural gas exporter Gazprom and pave the way for a multi-commodity energy supplier business where they can influence end-user prices directly.