MOSCOW, September 29 (RIA Novosti) - A project to pump Russian gas to South Korea through a North Korean pipeline has been suspended due to the deterioration in inter-Korean relations, the South Korean Yonhap news agency said on Tuesday.

Choo Kang-soo, head of South Korea's state-run energy company Kogas, said Seoul would not build the pipeline through North Korea until Pyongyang officially asked the South to do so.

Last year, Kogas and Russia's Gazprom agreed a $90 billion deal to import to South Korea up to 10 billion cubic meters of gas a year, a fifth of Kogas's needs, for 30 years after 2015 through a $3 billion pipeline that would run from Russia's Pacific port of Vladivostok across North Korea.

With plans for the pipeline now on hold, Seoul has proposed liquefied natural gas (LNG) imports to the country from Vladivostok by ship.

South Korea relies almost entirely on imports for its liquefied natural gas needs. It has a diversified gas transportation network, linking coastal liquefied natural gas terminals to key consumption centers across the country, which makes it possible to use natural gas not only in electricity generation but also in the industrial and the utility sectors.