MOSCOW (Reuters) - The first Russian-built ice-class liquefied natural gas (LNG) carrier has entered sea trials, LSEG data showed on Friday, as part of Russia's efforts to raise global LNG market share despite U.S. sanctions.

The tanker, named Alexey Kosygin after a Soviet statesman, was built at the Zvezda shipyard and is due to join the fleet of vessels for Russia's new Arctic LNG 2 plant, which has been delayed because of the U.S. sanctions over the conflict in Ukraine.

The U.S. Treasury has also placed sanctions on the new vessel, which Russia's leading tanker group Sovcomflot ordered to be built at Zvezda, Russia's most advanced shipbuilding yard. LSEG ship-tracking data shows it is anchored near the Pacific port of Vladivostok.

Sovcomflot has not replied to a request for comment.

Novatek, which owns 60% of Arctic LNG 2, has said 15 Arc7 ice-class tankers that are able to cut through two metre (6.5 ft) thick ice to transport LNG from Arctic projects, will be built at Zvezda shipyard.

According to a source familiar with the matter, Novatek shut down commercial operations at the first and only operational train of its Arctic LNG 2 project in October with no plans to restart it during winter.

Ice-class tankers usually have double hulls - strengthened structures to withstand the pressure of ice - and reinforced propellers.

So far, only three suitable gas tankers have been built for Arctic LNG 2, according to public information: the Alexey Kosygin, Pyotr Stolypin and Sergei Witte vessels.

Six more Arc7 tankers were due to be built by Hanwha Ocean, formerly Daewoo Shipbuilding & Marine Engineering, including three for Sovcomflot and three for Japan's Mitsui O.S.K. Lines.

However, the three tankers ordered by Sovcomflot were cancelled due to the sanctions against Russia, Hanwha said last year in regulatory filings.

(Reporting by Vladimir Soldatkin; additional reporting by Gleb Stolyarov; editing by Barbara Lewis)