China and Russia deepened their energy ties Nov. 9 with a second blockbuster deal that lessens Russian reliance on Europe and would secure almost a fifth of the gas supplies China needs by the end of the decade, Bloomberg said Nov. 9.

Russian President Vladimir Putin and Chinese President Xi Jinping signed the preliminary gas supply agreement in Beijing the day before U.S. President Barack Obama arrived in the Chinese capital for the Asia-Pacific Economic Cooperation summit. The deal is slightly smaller than the $400 billion accord reached earlier this year, shortly after Russia’s annexation of Crimea.

Russian oil firm OAO Gazprom is negotiating the supply of as much as 30 billion cubic meters (Bcm) of gas annually from developments in West Siberia to China over 30 years, it said Nov. 9. At the same time, another Russian producer, OAO Rosneft, agreed to sell a 10% stake in a Siberian unit to state-owned China National Petroleum Corp. (CNPC).

The export of new supplies to Asia increases the possibility of a glut on global energy markets by early next decade. Once deliveries begin, China would supplant Germany as Russia’s biggest gas market, even as relations have soured with the U.S. and Europe over the Ukraine crisis.

The gas glut could resemble what’s happened in the iron ore industry, according to Kenneth Courtis, chairman of Starfort Holdings and former Asia vice chairman at Goldman Sachs Group Inc. (NYSE: GS). That industry has seen miners ramp up production in the teeth of falling prices, shaking out higher cost suppliers.

“There is going to be new supply of natural gas coming from everywhere,” including Australia, the U.S., Canada and Mozambique, Courtis wrote in an email.

The accord “will make Russia rely more on China both economically and politically,” said Lin Boqiang, director of the Energy Economics Research Center at Xiamen University.

“China is probably the only country in the world that has both the financial ability and the market capacity to consume Russia’s huge energy exports on a sustainable basis over a long period of time,” Lin said Nov. 10 by phone.

It gives Putin an opportunity to show Europe and the U.S. that his country won’t be isolated over Ukraine, he said.

The two deals could account for almost 17% of China’s gas consumption by 2020, Gordon Kwan, a Hong Kong-based analyst at Nomura Holdings Inc. (NYSE: NMR), wrote Nov. 10 in an email.

Russia might start selling gas to China within four to six years as part of its agreement with CNPC, Alexey Miller, the CEO of Gazprom, told reporters in Beijing.

“Together we have carefully taken care of the tree of Russian-Chinese relations,” Xi Jinping said Nov. 9 at a meeting with Putin at the economic forum. “Now fall has set in, it’s harvest time, it’s time to gather fruit.”

A second China-Russia agreement adds to pressure on LNG suppliers, mainly in Australia where costs to build new plants are high, Adrian Wood, a Sydney-based analyst at Macquarie Group Ltd. (ASX: MQG.AX), said Nov. 10 by phone.

“There is a general view out there that China is going to underwrite all these projects, that Chinese demand is insatiable,” Wood said. “We’ve never shared that view. This is going to certainly weigh on demand, and therefore there will be even more competition for customers.”

Putin called the earlier agreement between state-run Gazprom and its Chinese partners “epochal.”

CNPC also signed an initial agreement with Rosneft to acquire 10% of the Vankorneft business. Russia and China also are considering gas supplies from Russia’s Far East, Gazprom’s Miller said.

Under the agreement earlier this year, China will import 38 Bcm of gas from Russia annually over three decades, starting as soon as 2018.

Gas will account for more than 10% of China’s energy consumption by 2020, compared with 6% currently, according to the National Development and Reform Commission, China’s national economic planner.