SEOUL, South Korea - North Korea today announced for the first time that it has nuclear arms and rejected moves to restart disarmament talks anytime soon, saying it needs the weapons as protection against an increasingly hostile United States.

The communist state's pronouncement dramatically raised the stakes in the two-year-old nuclear confrontation and posed a grave challenge to President Bush, who started his second term with a vow to end North Korea's nuclear program through six-nation talks.

"We ... have manufactured nukes for self-defense to cope with the Bush administration's ever more undisguised policy to isolate and stifle the (North)," the North Korean Foreign Ministry said in a statement carried by the state-run Korean Central News Agency.

The claim could not be independently verified. North Korea expelled the last U.N. nuclear monitors in late 2002 and has never tested a nuclear bomb, although international officials have long suspected it has one or two nuclear bombs and enough fuel for several more.

Secretary of State Condoleezza Rice said North Korea should return to disarmament talks and avoid a path toward further international isolation. She said the world "has given them a way out and we hope they will take that way out."

"The North Koreans have been told by the president of the United States that the United States has no intention of attacking or invading North Korea," Rice told a news conference in Luxembourg. "There is a path for the North Koreans that would put them in a more reasonable relationship with the rest of the world."

Previously, North Korea had reportedly told U.S. negotiators in private talks that it had nuclear weapons and might test one of them. The North's U.N. envoy said last year that the country had "weaponized" plutonium from its pool of 8,000 nuclear spent fuel rods. Those rods contained enough plutonium for several bombs.

But today's statement was North Korea's first public acknowledgment that it has nuclear weapons.

North Korea's "nuclear weapons will remain (a) nuclear deterrent for self-defense under any circumstances," the ministry said. It said Washington's alleged attempt to topple the North's regime "compels us to take a measure to bolster its nuclear weapons arsenal in order to protect the ideology, system, freedom and democracy chosen by its people."

Since 2003, the United States, the two Koreas, China, Japan and Russia have held three rounds of talks in Beijing aimed at persuading the North to abandon nuclear weapons development in return for economic and diplomatic rewards. No significant progress has been made.

A fourth round scheduled for last September was canceled when North Korea refused to attend, citing what it called a "hostile" U.S. policy.

South Korea said today the North's decision to stay away from talks was "seriously regrettable." Foreign Ministry spokesman Lee Kyu-hyung said "we again declare our stance that we will never tolerate North Korea possessing nuclear weapons."

In recent weeks, hopes had risen that North Korea might return to the six-nation talks, especially after Bush refrained from any direct criticism of North Korea when he started his second term last month.

Today, North Korea said it decided not to rejoin such talks any time soon after studying Bush's inaugural and State of the Union speeches and after Rice labeled North Korea one of the "outposts of tyranny."

"We have wanted the six-party talks but we are compelled to suspend our participation in the talks for an indefinite period till we have recognized that there is justification for us to attend the talks and there are ample conditions and atmosphere to expect positive results from the talks," the ministry said.

Still, North Korea said it retained its "principled stand to solve the issue through dialogue and negotiations and its ultimate goal to denuclearize the Korean Peninsula remain unchanged."

In his Jan. 20 inaugural speech, Bush vowed that his new administration would not shrink from "the great objective of ending tyranny" around the globe.

In his State of the Union address earlier this month, Bush only mentioned North Korea once, saying Washington was "working closely with governments in Asia to convince North Korea to abandon its nuclear ambitions."