All eyes on China for tougher sanctions against nuclear N. Korea

China has so far stayed quiet in the ongoing debate over how to punish North Korea for its latest underground nuclear test, with the international community waiting to see whether, and if so how, Beijing will rein in its troublesome ally.

Despite repeated international warnings, North Korea conducted its third nuclear test by detonating what it called a miniaturized atomic device on Feb. 12, drawing a chorus of worldwide condemnations and prompting the United Nations Security Council to begin devising "appropriate measures" against it. The North also conducted nuclear tests in 2006 and 2009.

China, the North's only ally, had expressed clear opposition to the nuclear test, but it has yet to share its stance on possible stronger sanctions against Pyongyang. In the past, Beijing has been reluctant to back tougher measures against the North, often using its veto power as a permanent member of the Security Council.

Seoul and Washington, on the other hand, have agreed to push forward tougher measures to penalize the country at the "earliest possible date."