North Korea vows to build more nuclear bombs

A defiant North Korea vowed yesterday to build more nuclear bombs and start enriching uranium for a new atomic weapons programme after the UN Security Council imposed sanctions for its nuclear test.

Washington's top diplomat Hillary Clinton responded by saying that the United States intends "to do all we can to prevent continued proliferation by the North Koreans".

"The North Koreans' continuing provocative actions are deeply regrettable," she told reporters at Niagara Falls on the Canadian side of the border with the US.

The North earlier described Friday's sanctions resolution as a "vile product" of a US-inspired campaign and said it would never abandon nuclear weapons and would treat any attempt to blockade it as an act of war.

The 15-member Council voted unanimously Friday to slap tougher sanctions on the North to cripple its nuclear and ballistic missile programmes.

The hardline communist state, in a foreign ministry statement reported by its official news agency, said all new plutonium it extracts would be weaponised.

One third of used fuel rods from the Yongbyon reactor have so far been reprocessed into weapons-grade plutonium, it said.

"Secondly, we will start uranium enrichment," it said in its first admission that it has such a programme - a second route to a nuclear bomb.

In 2002, the North denied US claims that it was operating a secret uranium enrichment programme in addition to its admitted plutonium-based operation.

The plutonium-producing plants were shut down under a 2007 six-nation disarmament deal. But Pyongyang vowed to restart them after the Security Council in April condemned its long-range rocket launch.

"It has become an absolutely impossible option for the DPRK (North Korea) to even think about giving up its nuclear weapons," the statement said, adding that any attempted blockade would be considered an act of war "and met with a decisive military response."

It added: "No matter how hard the US-led hostile forces may try all sorts of isolation and blockade, the DPRK, a proud nuclear power, will not flinch from them."