According to Reuters and Associated Press, a South Korean national security adviser, Ra Jong Yil, said the proposal was at an early stage and needed to be discussed with allies and North Korea.

"Gas could be drawn from either Irkutsk (Siberia) or Sakhalin (east Russia)," Ra was quoted as saying to the Financial Times.

Ra added gas could fuel thermal power stations and provide a peaceful alternative to Pyongyang's nuclear program, which Washington claimed was aimed at producing atomic weapons.