North Korea said Wednesday, ahead of landmark talks with the United States, that a US missile defense shield will set off a new nuclear arms race.

The new diplomatic attack on the United States came as the US government said it wanted to see signs in talks due to start on Thursday in New York that North Korea is "serious about moving forward."

But the North's UN envoy said the United States was aiming through its proposed missile defense shield to gain "absolute nuclear superiority and global hegemony over the other nuclear power rivals."

The ambassador, Sin Son Ho, said the shield showed the United States has no "moral justifications" to lecture other countries about proliferation.

"In this current changing world, one can easily understand that this dangerous move will eventually spark a new nuclear arms race," Sin said of the shield which the United States wants to build over eastern Europe. Washington says the shield is aimed at preventing attacks by rogue states such as Iran.

"This shows that the world's largest nuclear weapon state has lost its legal or moral justifications to talk of proliferation issues before international society, on whatever ground," the envoy added.

North Korea and the United States are to hold two days of talks in New York from Thursday on issues including the North's nuclear arsenal.

Vice foreign minister Kim Kye-Gwan is leading the North's delegation at the New York talks. Kim arrived in the United States late Tuesday.

Kim and US envoy for North Korea, Stephen Bosworth, are expected to discuss improving US-North Korean ties and ways to relaunch six-nation talks on the North giving up its nuclear weapons.

Talks between North Korea and the United States, China, South Korea, Japan and Russia have been frozen since December 2008.

The North staged nuclear tests in 2006 and 2009 which sparked international concern and outrage.

US Secretary of State Hillary Clinton announced the New York talks on Sunday, two days after the nuclear envoys of South and North Korea held a surprise meeting on the sidelines of an Asian security conference in Bali, Indonesia.

In Washington, State Department spokesman Mark Toner said the Bali meeting had been "constructive" but that the communist state needs to do more.

"What we're looking for is in our mind a clear indication that North Korea is serious about moving forward," Toner told reporters.

The United States will be watching to see if North Korea will recommit to a 2005 agreement made at the six party talks "as well as take concrete and irreversible steps towards denuclearization," the spokesman said.

South Korea, a key observer in the new contacts between the North and the world superpower, has also demanded signs that its arch-rival is sincere about wanting good relations before it agrees to concrete action to help its beleaguered neighbor.

South Korea remains furious over a deadly attack last year on an island on the tense frontier between the two.

The North's disclosure in November that it had a uranium enrichment plant, which could give it another way to make atomic weapons, has become a new complicating factor.

The North's official news agency, in a commentary Wednesday, said a peace agreement with the United States formally ending the 1950-53 war could become a "first step" to peace on the Korean peninsula and "denuclearization".

The North and South fought a bitter war in 1950-53, with the United States fighting with the South. The conflict ended 58 years ago on Wednesday with an armistice but no full peace treaty.

"It is impossible to wipe out the mutual distrust, nor is it possible to achieve a smooth solution of the issue of denuclearization, as long as there persists the hostile relationship" between North Korea and the United States, the news agency said.

burs-tw/jm