NORTH Korea has accused the United States of contributing to an "unpredictable" situation on the divided Korean peninsula and abusing its power in the United Nations Security Council to impose its "hostile policy" against Pyongyang.

North Korea is facing further UN sanctions for its underground nuclear test explosion two weeks ago, its biggest and most powerful to date, which prompted warnings from Washington. In December, it launched a long-range rocket.

"The US is to blame for the situation on the Korean peninsula which is inching close to an unpredictable phase now," So Se Pyong, North Korea's ambassador to the UN in Geneva, told the UN-sponsored Conference on Disarmament.

"The US should no longer be allowed to seriously infringe upon the independent right of the DPRK to use space for peaceful purposes nor should it be allowed to abuse the UN Security Council as a tool for executing its hostile policy toward the DPRK," he added, using the acronym for the Democratic People's Republic of Korea.

"The third nuclear test was carried out as part of the practical counter- measures for defending the country's sovereignty and security to cope with ruthless hostile behaviours of the US, which wantonly infringed upon the DPRK's legitimate right to satellite launch for peaceful purposes," Mr So said.