By Lee Chi-dong

WASHINGTON, April 4 (Yonhap) -- There are clear signs of a "subtle change" in China's approach toward North Korea, which may affect "the calculus" in regional security conditions, a former senior U.S. official said Thursday.

"Yes, there's a subtle shift in Chinese foreign policy...Over the short to medium term, that has the potential to affect the calculus in Northeast Asia," Kurt Campbell said at a forum hosted by the Johns Hopkins School of Advanced International Studies.

"You've seen it at the U.N. (Security Council). We've seen it in our private discussions and you see it in statements in Beijing," he added.

Campbell served as assistant secretary of state for East Asian and Pacific affairs for four years. He left the department in February.

He is one of key architects of the Barack Obama administration's policy of rebalancing diplomatic efforts and military presence toward Asia.

Campbell said North Korean officials are apparently noticing the mood change in Beijing.

"I don't think that subtle shift can be lost on Pyongyang," he said. "They need a close relationship with China for every conceivable reason. It's not in their strategic interest to alienate every country that surrounds them."

He said the U.S. and its regional allies -- South Korea and Japan -- are doing an efficient job in dealing with North Korea's military threats.

They have articulated that there is a bit of a gap between the language from Pyongyang and what's going on there actually, he said.

"The most important new ingredient has been a recognition in China that their previous approach to North Korea is not bearing fruit."

Campbell now works as chairman and CEO of The Asia Group. a strategic advisory and investment group specializing in the Asia-Pacific region.

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