China rebuffed on Friday a US claim that Beijing's approach to the Democratic People's Republic of Korea has failed, saying the key to solving the Korean Peninsula nuclear issue does not lie with China.

"The cause and crux of the Korean Peninsula issue does not lie with China, nor does the key to solving the issue," Foreign Ministry spokeswoman Hua Chunying said at a news briefing.

Still, Hua said China will seek a solution, calling for joint efforts by all sides under the framework of the Six-Party Talks. The talks, which brought together the DPRK, the Republic of Korea, the United States, China, Japan and Russia, stalled in December 2008.

US Secretary of State John Kerry said in a phone conversation with Foreign Minister Wang Yi on Thursday that China's approach to the DPRK "has not worked and we cannot continue business as usual".

China has said it was not notified before the DPRK conducted what it said was a hydrogen bomb test on Wednesday and "firmly opposed" the test.

The Foreign Ministry said in a statement on Friday that Wang told Kerry that Beijing is willing to communicate with all parties, including the US, on the situation on the Korean Peninsula.

Also on Friday, Reuters cited a source as saying that the DPRK is seeking a peace treaty involving the US, China and the ROK to formally end the Korean War, and will not stop its nuclear tests until it gets one.

"This explosion is mainly for the United States to see," the source said, referring to the nuclear test. "The main objective is to persuade the United States to enter into four-country negotiations to end the war so that there can be everlasting peace on the Korean Peninsula."

Fan Jishe, a researcher of US studies at the Chinese Academy of Social Sciences, said, "China has done much more than what it should do on the issue." He said the US did not want to make tangible efforts, including talking about signing a peace treaty, but sought to shift its responsibilities to China.

Xinhua News Agency said in a commentary on Friday that "hostile US policy is the key reason behind the DPRK's nuclear brinkmanship".

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