China should work harder to keep peace between the two Koreas because an independent and peaceful North Korea could serve as a buffer zone between China and the US.

China and North Korea have made groundbreaking progress in bilateral economic and trade cooperation this year, especially established a special economic zone in the border area.

But China should do more to push North Korea to transform itself from a "nuclear crisis country" to a "peaceful developing country," which could prevent the US, Japan and South Korea from taking advantage of any confrontational incident to ferment a war.

China should facilitate economic reform in North Korea by increasing its investment and encourage the US, Japan and South Korea to open up their doors to North Korea, rather than using blockades and sanctions.

Beijing should make it clear to North Korea, South Korea, the US and Japan that peace in North Korea is important to China's core national interests.

China should sternly warn the North not to take any provocative action against the South and refrain itself in its response from any provocations from the South.

Meanwhile, China should also send a clear message to the US and Japan not to encourage South Korea to take any aggressive actions against the North.

China should make it crystal clear that anyone who uses the Yeonpyeong incident as an excuse for further provocative actions is playing with fire.

The author is a professor of Tsinghua University. His blog: http://blog.sina.com. cn/lixiguang2010, follow him on: http://t.sina.com.cn/ MyNewsToday. xiguang@ tsinghua.edu.cn