UNITED NATIONS - The five nuclear powers on the Security Council agreed Saturday to eliminate their nuclear arsenals, as part of a new disarmament agenda approved by 187 countries.
The agreement by the signatories to the Nuclear Nonproliferation Treaty was reached after all-night deliberations and intense pressure on Iraq and the United States to settle a dispute over Baghdad's compliance with U.N. sanctions.
''Today is a great day for the cause of nuclear nonproliferation and nuclear disarmament,'' said Algerian U.N. Ambassador Abdallah Baali, the conference president, as he banged the final gavel to loud applause.
Although the agreement gives no timetable, and delegates said it would take many years to achieve a nuclear-free world, it marked the first time the major nuclear powers had publicly affirmed their obligation to disarm.
The five-year review conference for the global treaty - aimed at controlling and ultimately eliminating nuclear weapons - required a consensus, and the U.S.-Iraq dispute threatened to sabotage approval of a final document.
Signaling the importance Washington placed on the issue of Iraq's compliance with nuclear agreements, U.S. Assistant Secretary of State Robert Einhorn, who is in charge of nonproliferation, flew to New York to take part in the final talks.
Hours after his arrival, Canadian Ambassador Chris Westdal, who had worked through the night, announced an agreement to applauding delegates, saying ''the last piece in our puzzle is complete.''
Delegates to the conference said the new agreement was significant because it marked the first time in 15 years that the signatories to the nonproliferation treaty have reached consensus on moving forward with nuclear disarmament.
Secretary-General Kofi Annan said it ''marks a significant step forward in humanity's pursuit of a more peaceful world - a world free of nuclear dangers, a world with strengthened global norms for nuclear nonproliferation and disarmament.''
On Thursday, the five nuclear powers - the United States, Russia, Britain, France and China - agreed to ''an unequivocal undertaking'' to eliminate their nuclear arsenals.
The NPT, which came into force in 1970, has only four holdouts: India and Pakistan, which conducted rival nuclear tests in 1998, Israel, which is believed to have nuclear weapons, and Cuba.
Delegates repeatedly stressed the importance of getting those nations to sign - a step many concede is crucial to the cause of disarmament.
The final document reaffirmed ''the importance of Israel's accession to the NPT'' and urged India and Pakistan, despite their nuclear tests, to become parties to the treaty ''as non-nuclear weapon states.''
But China's U.N. Ambassador in Geneva, Hu Xiaodi, was critical, saying the document did not ''fully reflect the current international situation, nor does it call for the removal of fundamental obstacles to nuclear disarmament.''
Hu cited a host of issues that weren't addressed in the final document - the expansion of NATO, the absence of any reference to no first use of nuclear weapons or U.S. plans for a limited missile defense system.
Nonetheless, the delegates did take other important steps leading up to a total ban on nuclear weapons, including a moratorium on testing pending activation of the Comprehensive Nuclear Test Ban Treaty, further reductions of tactical nuclear weapons, increased transparency on reporting information about nuclear arsenals and taking weapons off ''hair-trigger'' alert.
They also agreed to permanently and irreversibly remove plutonium and uranium from nuclear warheads, and to negotiate within the next five years a treaty banning the production of weapons-grade nuclear material.
The U.S.-Iraq dispute centered on Iraq's compliance with U.N. sanctions requiring that Iraq's facilities for producing nuclear, chemical and biological weapons be shut down. The United States maintains that Iraq has not adequately accounted for its weapons programs.
Iraq's U.N. Ambassador Saeed Hasan initially said Baghdad would accept the International Atomic Energy Agency's January inspection of its nuclear reactors under the NPT treaty - but was vehemently opposed to U.S. demands for a statement that the IAEA inspection would not substitute for its Security Council obligations.
Under the compromise language, the conference noted an April 24 statement by the IAEA director-general that since Iraq has suspended weapons inspections since December 1998 ''the agency has not been in a position to provide any assurance of Iraq's compliance'' with the U.N. sanctions.
At the final plenary session of the conference, Hasan entered a reservation on the compromise, reiterating that there was ''no reason'' to include Iraq or the Security Council resolution in the document.
But without naming Iraq, U.S. Ambassador Robert Gray said it was important that the conference expressed ''profound concern about cases of noncompliance.''