North Korea's sole ally, China is reportedly flexing its diplomatic muscle to get the communist state to call off a highly anticipated test.

Choi You-sun has more on Beijing's efforts, including its talks with Washington and Seoul. A high-ranking official in Seoul says China is serious about the expected negative outcome of a third North Korean nuclear test and is, in its own way, persuading its ally to call off the test.

The official adds that Beijing will continue to make efforts to stop the Kim Jong-un regime until the very last minute, even if Pyongyang does actually test its nuclear capability.

Beijing is known to have been employing various strategies to persuade Pyongyang to call off the test, including indirect warnings that it will cut off aid to the North.

Earlier this week, South Korea's top nuclear envoy Lim Sung-nam discussed Seoul and Beijing's cooperation in deterring Pyongyang's provocative behavior with Chinese officials, including his counterpart Wu Dawei.

During the talks, Lim and Wu shared the view that the North must not conduct a third nuclear test, and they agreed to work together on denuclearization of the Korean Peninsula.

Following his trip to Beijing, Lim declined to comment on whether the two sides had also discussed putting additional sanctions on North Korea if the regime goes ahead with the test.

While Seoul and Washington have begun talks on that subject, Beijing is reluctant to do so, thinking it could push Pyongyang to move forward with the provocation.

U.S. Secretary of State John Kerry, meanwhile, spoke with Chinese Foreign Minister Yang Jiechi, and the two sides vowed to stay united in urging North Korea to honor its UN Security Council commitments and refrain from further provocations.

They also discussed the recent UN resolution, which states there would be significant action by the international community if North Korea provokes again.

China, which had often defended its long-time ally in the face of international condemnation in the past, cooperated with the U.S. in expanding sanctions on the Kim Jong-un regime for its recent rocket launch.

Choi You-sun, Arirang News.

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