WASHINGTON — The Bush administration announced Saturday that it had removed North Korea from a list of state sponsors of terrorism in a bid to salvage a fragile nuclear deal that seemed on the verge of collapse.

Sean McCormack, the State Department spokesman, said that the United States made the decision after North Korea agreed to resume disabling a plutonium plant and to allow some inspections to verify that it had halted its nuclear program as promised months earlier.

The deal, which the Bush administration had portrayed as a major foreign policy achievement, began slipping away in recent weeks in a dispute over the verification program. Just days ago, North Korea barred international inspectors from the plant.

The decision to remove North Korea from the terror list was a dramatic moment for President Bush, who had called the country part of an “axis of evil” and had only reluctantly ordered administration officials to engage in negotiations, saying that the United States had made deals with the nation’s leaders before without winning enough concessions.

That calculus changed in 2006, when North Korea exploded a nuclear device.

But Mr. Bush is already having trouble selling the new agreement to his own party. Republican lawmakers, including the presidential nominee, Senator John McCain, quickly expressed concern, complaining that North Korea had yet to demonstrate that it was serious about adhering to its commitment to denuclearize.

Senator Barack Obama, the Democratic nominee for president, called the deal “a modest step forward” in dismantling North Korea’s nuclear weapons program. Other Democrats said they welcomed the agreement but noted that it did not go much beyond an agreement President Clinton reached with North Korea in 1994, which the Bush administration, including Secretary of State Condoleezza Rice, criticized as inadequate.

Bush administration officials, trying to head off potential criticism that they were simply seeking a foreign policy victory in their last months, said the agreement was the best the United States could get at this time.

Ms. Rice “very strongly feels that it is our own responsibility, until Jan. 20, 2009, to act as good stewards of the national interest,” Mr. McCormack said during a news conference.

In the most significant part of the accord announced Saturday, North Korea agreed to a verification plan that would allow United States inspectors access to its main declared nuclear compound, at Yongbyon; international inspectors have worked at the site on and off for years. But the deal puts off decisions on the thorniest verification issue: what would happen if international experts suspected the North was hiding other nuclear weapons facilities, particularly those related to uranium enrichment.

The United States wanted the North to agree to inspections at sites that raised suspicions, but North Korea balked. The new agreement calls for United States inspectors to be granted access to such sites “based on mutual consent” with North Korea.

Experts on North Korea say that the concession by the United States was probably necessary to achieve a deal, but that it no doubt will lead to future fights, since the North’s leaders will not want to give inspectors free rein to travel the country.

Patricia A. McNerney, one of the State Department negotiators, acknowledged that issue would probably lead to a hornets’ nest of problems. “Going into verification with North Korea will not be easy, we know that,” she said. “This is the most secret and opaque regime in the world.”

North Korea on Sunday welcomed its removal from Washington’s terrorism blacklist and said that it would resume disabling its nuclear weapons facilities, allowing American and United Nations monitors back into its main nuclear complex.

South Korea and Japan also hailed the agreement on Sunday. But hawkish politicians in Washington’s two main Asian allies, as well as relatives of people allegedly kidnapped by the Communist state, accused the United States of giving in to the North’s bad behavior.

“We are extremely disappointed with the United States, which we had believed would be a pillar of anti-terrorism and human rights,” said Choi Sung Yong, 56, head of the Abductees’ Family Union, which includes relatives of hundreds of South Koreans, mostly fishermen, allegedly abducted to the North.

Relatives of the South Korean and Japanese abductees have counted on Bush to use the terrorism blacklist as leverage to pressure the North Korean leader, Kim Jong Il, to return their missing family members.

North Korea, which has long sought international acceptance, had been pushing hard to get off the terror list. But Mr. McCormack made clear on Saturday that North Korea is still subject to numerous economic sanctions.

The agreement follows weeks of intense negotiations and high-stakes brinkmanship, as North Korea, furious that the Bush administration had not removed it from the terrorism list as it agreed last summer, threatened to restart its plutonium-based weapons program and barred international inspectors from the Yongbyon plant. In Washington, State Department proponents of the deal, including Ms. Rice and her top North Korea envoy, Christopher R. Hill, battled critics inside and outside the administration who castigated them for trying to salvage the accord.

The administration has been at war with itself over whether to go ahead with the North Korea pact despite objections from critics in the office of Vice President Dick Cheney, and even some members of the State Department’s verification and compliance office. That rift spilled into the open at the news conference on Saturday, when a reporter asked Paula A. DeSutter, the assistant secretary of state for verification, compliance and implementation, how she responded to criticism of the deal from John R. Bolton, her former boss at the State Department.

Ms. DeSutter did not defend the accord, saying simply, “John is the epitome of a skeptical policymaker, and that’s appropriate.”

Despite the internal fights, Ms. Rice convinced President Bush last week that this was the best the administration could get in its remaining time in office. But as late as Friday, things remained up in the air, said one administration official, who, like several other officials and diplomats interviewed for this article, spoke on the condition of anonymity because of the delicacy of the issue. Another senior administration official described the internal deliberations as a “close call.”

Senator McCain said in a statement that he would not support the deal until he got some questions answered. “I expect the administration to explain exactly how this new verification agreement advances American interests and those of our allies,” he said. He added that he was “concerned that this latest agreement appears to have been reached between Washington and Pyongyang, and only then discussed with our Asian allies in an effort to garner their support.”

Representative Ileana Ros-Lehtinen, Republican of Florida, issued a statement strongly criticizing the deal. “I am profoundly disappointed,” she said. “By rewarding North Korea before the regime has carried out its commitments, we are encouraging this regime to continue its illicit nuclear program and violate its pledge to no longer provide nuclear assistance to extremist regimes.”

Two of the Bush administration’s main criticisms of the 1994 accord were that it did not mandate the removal of nuclear material from North Korea and that international inspectors were limited to Yongbyon.

The 1994 accord collapsed in 2002 after the Bush administration accused North Korea of circumventing the agreement by pursuing a second path to a bomb, based on enriching uranium. The White House said at the time that it would require full verification that any uranium program had been halted, though later the intelligence community expressed some doubts about how far the program had gotten.

Although the new agreement leaves open the possibility of future inspections outside Yongbyon, it leaves vague what mechanism would be used to determine the status of a uranium program.

The North has agreed in principle to give up its nuclear material and any weapons, but that seems almost certain to be subject to negotiations with the next president. During the Bush administration, North Korea is believed to have produced enough bomb-grade plutonium for six or more nuclear weapons.

Bush administration officials have been consulting about the latest deal with its partners in the so-called “six-party” talks, the group including Russia, South Korea and Japan that negotiated the agreement in 2007 for the North to halt its nuclear activities.

Diplomats said that Japan had expressed reservations about removing North Korea from the terror list because the North still had not addressed all of their concerns about abductions of Japanese citizens decades ago.

After the official announcement on Saturday, Japan’s finance minister, Shoichi Nakagawa, called the American decision “extremely regrettable.”

South Korea has been more supportive.

“We welcome the agreement because we believe this will help put the six-party negotiations back on track and eventually lead to the dismantlement of North Korea’s nuclear programs,” said Kim Sook, South Korea’s main nuclear envoy, during a news conference in Seoul on Sunday.

The South Korean foreign minister, Yu Myung-hwan, had stressed Friday that if the six-party negotiations fell apart now, the next administration would have difficulty restarting them.

Gary Samore, a nonproliferation expert in the Clinton administration, characterized the deal as probably the best that could be gotten at this time, but warned of stormy times to come.

“Every agreement you ever have with the North Koreans always contains certain ambiguities, and that ends up being the basis for which you have the next round of talks,” he said. “It’s always two steps forward and one step back.”

For instance, he said, besides the issue of access to suspected nuclear sites, the United States and North Korea appear to have fudged the critical issue of whether American inspectors will be allowed to take all the samples they want out of the country to foreign laboratories for inspection.

According to a fact sheet issued by the Bush administration, the two sides agreed “on the use of scientific procedures, including sampling and forensic activities,” although the sheet doesn’t say where those tests would be done.

Mr. Bolton, the former United States ambassador to the United Nations under Mr. Bush, said that the Bush administration had “punted” the hardest issue, that of inspections beyond declared nuclear sites.

“This means that North Korea has a veto over everything beyond Yongbyon,” he said, “so that’s a clear victory for North Korea.”