Russian and Chinese officials are due to strike a deal on Tuesday allowing China to receive Russian gas worth USD 400 B over the next 30 years, a Russian daily reports.

Citing sources from the energy company Gazprom, Russia's Izvestiya argues that the forthcoming agreement envisages that 38 bcm of gas a year be supplied to China. The three-decade span of the contract means the quantity might reach 1140 bcm.

This is somewhere between a fourth and a fifth of Europe's yearly deliveries from Russia, which are estimated at 161.5 bcm for 2013.

Gas will be traded on average European prices, or USD 350 to 380 per thousand cubic meters. Izvestiya quoted the Gazprom source as saying that the positions of China and Russia on the pricing formula are "very close".

The reported deal seems to coincide with Russian President Vladimir Putin's visit of Shanghai, where is to take part in a conference on strengthening trust among Asian countries.

His trip, alongside news of the gas agreement, come amid heightened tensions between Russia and the West over the Ukraine crisis.

Europe has repeatedly issued a threat to impose economic sanctions on Russia as a continued response to the standoff, even though opinions on that matter are divided on the continent. This could stop Russia-originated gas glow.

Ukraine's refusal to pay for its gas, on the other hand, is posing a risk for the EU's energy supplies, as deliveries via the country's territory might come to a halt.

Moscow has repeatedly stated it would increase cooperation with other partners such as China and India if the EU pursues its efforts to isolate it.