Beijing: In a rare public display of annoyance towards North Korea, China Tuesday said it will not support its reclusive ally's pursuit to acquire nuclear weapons and missiles but will provide security assistance if war breaks out in the Korean peninsula.

"If the DPRK (Democratic People's Republic of Korea) seeks development and security, we are prepared to help and provide support," Chinese Foreign Minister Wang Yi said in his annual briefing.

"At the same time we have an unwavering commitment for denuclearisation of the Korean peninsula and we will not accommodate DPRK's pursuit of nuclear and missile programmes," Wang said, distancing China from North Korean leader Kim Jung-un's recent directive to officials to keep the nuclear weapons ready to use in the aftermath of the UN sanctions.

This is the first time China openly came out against North Korea, whose dictatorial regime has enjoyed its backing for long. Wang also said China, which looks exasperated with Kim Jong-un's antics, will implement UN sanctions against North Korea.

"China is a permanent member of the UN Security Council. We have the responsibility and capability to implement various resolutions passed by the Security Council, including Resolution 2270 concerning the DPRK," Wang said.

"In China's view, Resolution 2270 must be implemented in its entirety. Sanctions are just necessary means, maintaining stability is the pressing priority, and only negotiation can provide a fundamental solution," he said.

As the largest neighbour of the peninsula, China will not sit by and see a fundamental destruction to the stability of the Korean Peninsula, and will not sit by and see unwarranted damages to China's security interests, he said.