China’s top oil and gas producer, PetroChina, is scouring global markets for gas imports to avert a looming winter supply crunch but faces tough competition from South Korea and Japan.

The world’s top two buyers of liquefied natural gas are snapping up cargoes to compensate for shuttered nuclear plants as cold weather bites, and along with China have driven LNG prices to an eight-month high.

LNG spot prices are around $17.50 per mmBtu, up from around $15 per mmBtu in mid-September. PetroChina awarded a tender for four LNG cargoes for the winter, although the suppliers could not be confirmed.

“PetroChina has already been out in the market, pre-empting this higher winter demand – the cargoes are brought in relatively quickly, within three weeks or so, and now is the right time to buy,” said Tony Regan of energy consultancy Tri-Zen, based in Singapore.

As Beijing tries to ration supplies to residential users and cut demand from industrial consumers, China’s top suppliers are scrambling to hike output and boost overseas purchases before huge gas-fired heating systems in major cities such as Beijing switch on in mid-November.

Increases in imports must accompany the company’s efforts to boost output in the next few weeks, Liao Yongyuan, general manager of PetroChina’s parent, the state-owned China National Petroleum Corp (CNPC), urged.

CNPC needed to beef up the capacity of its gas pipelines this winter, Liao said in remarks published by China Petroleum Daily, CNPC’s official newspaper.