MOSCOW, May 4 (Reuters) - Russia plans to send some 35 billion cubic metres (bcm) of natural gas per year to China via Kazakhstan, the TASS news agency reported on Saturday citing Kazakhstan's envoy to Russia, disclosing the potential volumes for the first time.

Last year, Kazakhstan and Russia established a route for a future gas pipeline to support shipments between the two countries and to China.

"We want to make the most of our transit potential. The road map has been signed. We are talking about 35 billion cubic meters of gas (per year), which will be supplied to China," envoy Dauren Abayev told TASS, adding that talks on gas pricing are ongoing.

No other details on the future pipeline have been revealed.

The stated volume would be on par with the Power of Siberia pipeline now serving China. It is due to reach a capacity of 38 bcm by 2025.

The future pipeline via Kazakhstan would help Russia, hit by Western sanctions over the conflict in Ukraine, boost sales to Asia.

It would also ensure Kazakhstan secures supply for its central, northern and eastern regions.

However, no deal has yet been reached with China.

Moscow has been in painstaking talks with Beijing for years over gas exports, including via the Power of Siberia 2 designed to run via Mongolia, while experts say China will not need additional natural gas until after 2030.

Russian President Vladimir Putin is due to visit China later this month and energy issues are expected to be discussed. China is one of the biggest buyers of Russian oil.

Russia's pipeline gas exports to Europe, which used to be the main market for the country's oil and gas, almost halved last year.

Russian gas firm Gazprom has been the most tangible victim of the West's sanctions. It announced a $7 billion loss for 2023 on Thursday, its first annual loss since the late 1990s. (Reporting by Vladimir Soldatkin; editing by Angus MacSwan and Jason Neely)