WASHINGTON - If North Korea dismantles its nuclear weapons program, the Bush administration is ready to revive an offer of economic relations and a formal end to the Korean War as a way to help transform ties with that impoverished state, U.S. officials said yesterday.

But the White House was quick to insist that it would not reward North Korea for dropping its belligerent stance. Officials said they were not offering fresh incentives, only reviving previous offers that were lifted after North Korea acknowledged in October that it has a nuclear weapons program.

Before the United States found last year that North Korea has a uranium enrichment program, it was ready to go well beyond a 1994 pact worked out by the Clinton administration that froze the North's nuclear program. The new initiative was called a "bold approach."

With its recent defiant actions, though, North Korea risks further isolation. "The reality's changed," a senior State Department official said.

Pyongyang has balked at halting the uranium enrichment, expelled United Nations weapons inspectors, pulled out of the nuclear nonproliferation treaty and threatened to resume testing of long-range missiles.

Secretary of State Colin L. Powell said Friday that North Korea's conduct "will ultimately have to go to the U.N. Security Council," which could impose sanctions.

Still, the Bush administration has refused to take the prospect of closer ties off the table for future talks. And officials say the offer could be revived if North Korea meets conditions.

"Other things are possible in these relationships if North Korea verifiably and promptly eliminates [its nuclear] program," State Department spokesman Richard Boucher said yesterday.

But officials said that weekend talks in New Mexico between North Korean officials and Gov. Bill Richardson of New Mexico, a Democrat and former U.S. ambassador to the United Nations, failed to produce much hope that North Korea would yield to the point where a formal dialogue would be fruitful.

In South Korea yesterday, James A. Kelly, the U.S. assistant secretary of state for East Asian affairs, said: "Once we get beyond nuclear weapons, there may be opportunities with the U.S., with private investors, with other countries to help North Korea in the energy area."

In fact, this represents just part of a package of incentives the United States developed last year after a review of its policy toward North Korea. After initially showing no interest in continuing the Clinton administration's dialogue with North Korea, President Bush decided to resume it. But he chose to make it far more comprehensive, covering security issues as well as diplomatic, political and economic ties.

He sought improved North Korean compliance with its nuclear accords, controls over missile proliferation and cutbacks in the forces the North has arrayed along the demilitarized zone separating the two Koreas. North Korea also would have been pressed to ease repression and reform human rights.

Under the Bush approach, the United States would continue to supply food to prevent widespread starvation but seek better monitoring to ensure that the aid was not diverted to the North Korean military.

The United States was ready to offer a broad package of economic and diplomatic incentives to satisfy North Korea's craving for recognition and respect abroad. Trade barriers would be lowered, Western investment encouraged and liaison offices opened in the two capitals. Ultimately, full diplomatic relations would be offered.

Such a deal "was in the mix," a senior U.S. official said.

The terms were never spelled out publicly, but some have been confirmed by U.S. officials. Analysts questioned whether the administration was united behind the "bold approach," because disagreements over policy toward North Korea have persisted since Bush took office.

The United States was ready to offer "a transformed relationship" with North Korea that "put behind us the legacy of the last 50 years and looked forward," an official said. "There was a wide range of things we could do economically and a wide range of things North Korea could do to open itself up, as opposed to being a hermit country."

When Kelly went to Pyongyang in October, he told the North Koreans that the United States had been willing to pursue this "bold approach" but now could not, because its intelligence agencies had found that Pyongyang was pursuing a secret nuclear arms effort. To his surprise, North Korea defiantly acknowledged its program.

Some analysts speculate that the U.S. approach might have produced alarm in Pyongyang, because it would have exposed the North Korean populace to outsiders and could have eroded support for the Stalinist regime.

Still, "the North would have liked to get to the point of having embassies," even though this would mean an opening up, said Wendy L. Sherman, who negotiated with Pyongyang as a top State Department official in the Clinton administration. "North Korea so wants credibility and normal diplomatic relations [that its leaders believe] they can manage that risk."

In a joint statement with Japan and South Korea last week, the Bush administration said it was ready for a new dialogue with Pyongyang about how it could comply with the demand that it dismantle its nuclear weapons program. Officials say that a "freeze" is no longer sufficient and that North Korea must show it is giving up hopes of becoming a nuclear power.

U.S. intelligence agencies believe North Korea has enough fuel to produce two nuclear weapons, if it does not already have them. If it begins reprocessing spent fuel at its Yongbyon nuclear reactor, it could produce enough plutonium for a half-dozen bombs within months, U.S. officials say.

If a dialogue with North Korea does begin, U.S. officials say they would proceed cautiously and slowly, mindful of reluctance in Congress to offer new aid to the North.

Three Republican senators and a Democrat introduced a bill yesterday to reimpose sanctions against North Korea and require the same verification and inspection rules as those imposed by the United Nations on Iraq.

"We would not go right back to the Agreed Framework," a senior State Department official said, referring to the name given to the Clinton administration's 1994 pact, which offered to supply North Korea with fuel oil and relatively safe nuclear power plants in exchange for a halt in its nuclear weapons program.