The United States declined comment Friday on a phone conversation between President Park Geun-hye and Chinese President Xi Jinping in which the Chinese leader repeated calls for dialogue to resolve tensions on the Korean Peninsula without mentioning sanctions on North Korea.

"We are not going to comment on conversations that took place between China and ROK," Katina Adams, a spokesperson at the U.S.

State Department, said in response to a request for comment from Yonhap News Agency.

It was the first time that Park and Xi have spoken to each other since the North's Jan. 6 nuclear test. It also came amid mounting calls for China to use more of its leverage with Pyongyang to rein in its recalcitrant neighbor.

But Xi repeated China's existing positions that the Korean Peninsula should be free of nuclear weapons and all relevant parties should deal with the situation in a "cool-headed" manner and stick to the principle of dialogue and negotiations to resolve problems.

That is believed to be falling short of U.S. expectations.

The U.S. has worked hard to drum up Chinese support for meaningful punishment of the North for its latest nuclear test.

Chinese cooperation is key to putting together strong sanctions on Pyongyang as China is one of the five veto-holding permanent members of the U.N. Security Council and the main provider of food and fuel for the North. (Yonhap)