UNITED NATIONS — A monthlong conference aimed at curtailing the spread of nuclear weapons ended in failure Friday after being scuttled by arguments among the United States, Iran and Egypt.
Representatives of more than 150 nations convened at U.N. headquarters to seek ways to stop more countries from developing nuclear weapons, prevent terrorists from acquiring them, and get a renewed commitment from atomic powers -- especially the United States -- to significantly reduce their stockpiles.
But strong disagreements over priorities prevented substantive efforts to address the gaps between the world's nuclear haves and have-nots.
The United States tried to keep the focus on alleged nuclear threats from Iran and North Korea instead of its pledges to whittle down its own arsenal.
Iran, which contends that its atomic program is strictly for generating electricity, refused to discuss proposals to restrict access to nuclear fuel and objected to being singled out as a "proliferation concern." And Egypt joined Iran in demanding that the conference address Israel's nuclear status and declare the Middle East "a nuclear-free zone."
"The conference after a full month ended up where we started, which is a system full of loopholes, ailing and not a road map to fix it," Mohamed ElBaradei, the head of the International Atomic Energy Agency, told reporters in Vienna as the conference fizzled to a close.
U.N. Secretary-General Kofi Annan launched the conference -- a review of the 1970 Nuclear Nonproliferation Treaty -- on May 2, telling delegates that "the consequences of failure are too great to aim for anything less" than new measures to curb the spread of nuclear weapons and reduce the number of existing arms.
Under the treaty, atomic powers pledged to dismantle their arsenals and transfer nuclear know-how for generating electricity to other nations, in exchange for vows from those countries not to develop nuclear weapons. Reviews of the treaty are held every five years.
But critics say that not only are the nuclear powers not living up to their side of the deal, they are now seeking to restrict sensitive technology that other countries have a right to. The U.S. and some other nuclear powers, however, contend that increasingly stringent rules on transferring technology are needed to keep weapons out of terrorists' hands.
Annan said Friday that conference participants had "missed a vital opportunity" to strengthen the world's collective security and urged leaders to take up the issues again at a September summit at the U.N.
Conference president Sergio de Queiroz Duarte of Brazil acknowledged that "very little had been accomplished," but said the meeting was not a total failure. The month of discussions forced leaders to debate their differences even if they did not solve them, and paved the way for future talks, he said. Asked why the conference collapsed, he responded, "I think you can write several books on that."
A number of diplomats put much of the blame for the deadlock on the United States.
Washington's position has changed since the last conference in 2000, during the Clinton administration. The U.S. has refused to reaffirm the 13 steps toward nuclear disarmament it agreed to in 2000, or allow discussion of Israel's nuclear status.
Israel is widely thought to have nuclear weapons and, along with declared atomic powers India and Pakistan, is not a signatory to the nonproliferation treaty. North Korea withdrew from the pact in 2003 and has declared that it possesses nuclear weapons, though it has yet to test one.
Critics pointed out that during the monthlong conference, the White House asked Congress to fund research on a nuclear "bunker-buster" bomb that could destroy buried weapons stockpiles -- a move contrary to the treaty's intentions.
"If governments simply ignore or discard commitments whenever they prove inconvenient, we will never be able to build an edifice of international cooperation and confidence in the security realm," the head of Canada's delegation, Ambassador Paul Meyer, said in a speech to the conference. "We believe this is a treaty worth fighting for, and we are not prepared to stand idly by while its crucial supports are undermined."
U.S. negotiators tried to keep the conference focused on how other countries had breached the nonproliferation treaty, and how to stop that from happening again. In particular, it took aim at North Korea and Iran.
Iran has been chastised by the IAEA for not disclosing nuclear activities going back two decades, but inspectors have not concluded that Tehran is trying to build a nuclear bomb. Iran has denied that it has a weapons program.
Jackie W. Sanders, a lead U.S. negotiator at the conference, said Iran's violations were clear-cut.
"Iran's nuclear weapons program, previously shrouded in secrecy and deceit, has been exposed, as have Iran's violations of its IAEA obligations," she said.