ULAN BATOR, Jan. 18 (Xinhua) -- Mongolian Prime Minister Ukhnaa Hurelsukh said Wednesday that his government is willing to cooperate with China on its Tavan Tolgoi coking coal mine.

Hurelsukh made the remarks when asked about Tavan Tolgoi after concluding his official visit to South Korea from Jan. 15 to 17.

"The issue of Tavan Tolgoi is our internal political issue," he said. "Mongolia will only export its Tavan Tolgoi coal to China. So we have to cooperate with China," he said.

With a total estimated reserve of 6.4 billion tons, Tavan Tolgoi is one of the world's largest untapped coking and thermal coal deposits. The deposit is situated in the South Gobi desert, about 240 km north of the Chinese border.