BEIJING - Foreign Ministry spokesman Hong Lei said Thursday that China is willing to make joint efforts with Japan to boost bilateral relations.

Hong made the remark when asked about reports of a possible step-down of Japan's embattled Prime Minister Naoto Kan.

"We have noticed those reports. It's an internal matter for Japan," said Hong, adding that China is willing to work with Japan to promote the bilateral mutually beneficial strategic partnership.

Kan on Thursday survived a no-confidence motion brought by the conservative opposition after he pledged to step down once the country has recovered from the March 11 quake.