The two countries' foreign ministers condemned last week's test but said any action against North Korea had to be agreed at the United Nations, where Russia and China have the right of veto as permanent members of the Security Council.

"We are against the carrying out of a nuclear test in North Korea," Chinese Foreign Minister Yang Jiechi told a joint news conference after talks with Russian Foreign Minister Sergei Lavrov in Moscow.

"The U.N. Security Council should give an adequate response . . . but the action should be directed towards peace on the Korean peninsula," he said.

Lavrov said China and Russia had agreed that it was "vitally important not to . . . allow the situation to be used as a pretext for military intervention."

North Korea's latest test, its third since 2006, prompted warnings from Washington and others that more sanctions would be imposed on the isolated state.

The U.N. Security Council has only just tightened sanctions on Pyongyang after it launched a long-range rocket in December.

The North is banned under U.N. sanctions from developing missile or nuclear technology after its 2006 and 2009 nuclear tests.