But in a speech to the U.N. General Assembly, Vice Foreign Minister Pak Kil-yon said the Korean peninsula could only be denuclearized if the United States abandoned a policy of "confrontation" with Pyongyang.

Pak's speech came less than four weeks after the isolated communist state said it was in the final stage of enriching uranium, a process that would give it a second path to making a nuclear weapon. Hitherto it has mostly used plutonium.

In May, North Korea conducted a second nuclear test. Before that, U.S. officials said it had produced about 50 kg (110 pounds) of plutonium, which experts say would be enough for six to eight weapons.

North Korea has not shown, however, that it has a working nuclear bomb.

Charging that Washington had made nuclear threats against North Korea, Pak said Pyongyang had concluded it had no choice but to "rely on our dependable nuclear possession to ensure nuclear balance of the region."

But, he said, "The mission of our nuclear weapon is to deter a war. We will only possess nuclear deterrent to such an extent as to deter military attack and its threat against our country."

North Korea, he said, "while in possession of nuclear weapons, will act in a responsible manner in management, use and non-proliferation of nuclear weapons as well as in nuclear disarmament."

North Korea joined the nuclear Non-Proliferation Treaty in 1985 but left in 2003 after the United States confronted it with evidence Washington said pointed to a covert uranium enrichment program. The United States suspects the impoverished North has sought to sell its nuclear know-how abroad.

Pak said Pyongyang had always sought denuclearization of the Korean peninsula, but for that, "the U.S. administration must discard (its) old concept of confrontation and show the 'change' in practice, as it recently stated on several occasions."

The minister said it was North Korea's policy to react to dialogue with dialogue but he made no direct reference to nuclear talks among the two Koreas, China, Japan, Russia and the United States, which halted about a year ago.

China said on Monday its prime minister, Wen Jiabao, would visit North Korea next week, raising speculation the trip could help revive the stalled talks.

Pak launched a stinging attack on the U.N. Security Council, which approved expanded sanctions in June against North Korea after its nuclear test. He said the 15-nation body had "become more arrogant, resulting in further inequality and prevalent double standards in international relations."

Pak proposed that Security Council decisions should be submitted to the 192-nation General Assembly for approval.