Russia is to supply more gas to China under a new deal between the two countries. Presidents Vladimir Putin and Xi Jinping signed the paperwork on Sunday ahead of the two-day Asia Pacific Economic Cooperation (APEC) summit in Beijing.
It comes on top of a recent $400 billion gas deal.
And last month the two signed energy, trade and finance agreements – including a currency swap worth $25 billion intended partly to reduce the influence of the US dollar.
Putin has said he wishes to bolster ties with China to avoid isolation due to Western Sanctions over Ukraine.