BEIJING China warned North Korea on Friday it would not tolerate chaos on its doorstep, while blaming Japan for the tension between Asia's two largest economies.
Ties between Beijing and Pyongyang have deteriorated since North Korea conducted its third nuclear test in February. China signed on to U.N. sanctions in March, but remains the North's largest trading partner.
"China will never allow (anyone) to cause chaos and incidents on our home's doorstep and will never accept China's process of development from being disturbed and interrupted again," Foreign Minister Wang Yi said on the foreign ministry's website.
Wang reiterated China's stance that it promotes the denuclearization of the Korean peninsula, the solution of problems through dialogue and safeguards to peace and stability in the region.
"The current difficult situation in Sino-Japanese relations has been triggered and caused by Japan," Wang said in what the foreign ministry called a "special report" on China's path of peaceful development.
His remarks underscore the severe strain in Sino-Japanese ties caused by a dispute over tiny islands in the East China Sea believed to be surrounded by energy-rich waters.
Relations have also been overshadowed by what China calls Japan's refusal to admit to World War Two-era atrocities committed by its soldiers in China between 1931 and 1945.
"Japan should face up to reality, be cautious in its language and prudent in its actions, and refrain from doing things that undermine China's sovereignty and interests," Wang said.
"Japan's years of militarism and war of aggression have brought grave disaster to countries in Asia. Only when (it) learns from history can it open up to the future, only by adhering to the path of peace can it win its neighbors' trust."
Ties between the two countries suffered in September 2012 after Japan bought two of the disputed islets from a private owner, setting off a wave of protests and boycotts of Japanese goods across China.
On the United States, Wang repeated President Xi Jinping's earlier remarks that China wanted to build "a new brand of relations between major powers", based on principles of non-conflict, non-confrontation, mutual respect and cooperation.
(Reporting by Sui-Lee Wee; Editing by Clarence Fernandez)