Is China Getting Tough with N.Korea?

China has taken a series of economic sanctions against North Korea after the UN Security Council adopted Resolution 1874 over the North's recent nuclear test. Accounting for more than 70 percent of North Korea's international trade, China is seen to hold the key to success of the sanctions.

Chinese customs foiled an attempt to smuggle the rare metal vanadium, which can be used in missile casings, to North Korea. And Zhongkuang International Investment, a Chinese firm, has reportedly halted construction of facilities for a joint copper mine with Korea Mining Development Trading Corporation (KOMID), a North Korean firm blacklisted by the UNSC.

These measures were taken by China at around the time of this week's Strategic Economic Dialogue with the U.S. A joint press release at the talks said the two sides "emphasized the importance of implementing UN Security Council Resolution 1874 and resolving the nuclear issue on the peninsula through peaceful means."

Experts agree that China is fed up with North Korea since the latter's second nuclear test. Lee Tae-hwan, director of the Center for China Studies at the Sejong Institute, said, "Recent infrequent exchanges between North Korea and China reflect China's discontent."

But the handful of measures do not necessarily mean a change in China's basic North Korea policy. China is also worried about losing influence in Northeast Asia if the tide turns in favor of bilateral talks between Washington and Pyongyang and is therefore unlikely to cut the North adrift completely.