The world's nuclear tensions, distilled into words on paper, threatened on Wednesday to wreck a conference to strengthen the nonproliferation treaty, as diplomats labored on into the monthlong meeting's final days.

One of three committees ended its closed-door work with no recommendations to forward, in part because of Iran's objection to being singled out as a proliferation concern. "It's a sobering moment, a very bad signal," Chairman Laszlo Molnar (search) of Hungary said of his committee's failure late Tuesday.

The two other committees also wrangled behind closed doors over a long list of divistates under the 1970 treaty.

"The Americans have requested deletion of some fundamental issues. We cannot agree," Mexico's Luis Alfonso de Alba (search) told a reporter. Of prospects for an overall accord, the Mexican ambassador said, "It doesn't look good."

Those two committees ended their work Wednesday and forwarded proposals to the main conference body, but without consensus endorsement.

It was left to conference President Sergio de Queiroz Duarte (search) to try to cobble together some kind of final document by Friday, the meeting's final day. Disputes over the agenda had kept delegates from serious negotiation until last week.

With no input from a main committee, sharp differences on pressing issues, and so little time, it seemed the most Duarte might produce would be a vague declaration, rather than a concrete plan of action, since the gathering requires unanimity among the more than 180 treaty members.

"I am still trying to have the conference adopt whatever it can adopt," the Brazilian diplomat said as he rushed from one meeting to another.

Member states of the Nuclear Nonproliferation Treaty (search) meet every five years to identify weaknesses in the 1970 pact and win commitments on steps to remedy them. Though not legally binding, like a treaty, these consensus positions give a boost to nonproliferation initiatives.

Under the treaty, five nuclear weapons states -- the United States, Russia, Britain, France and China -- undertook to eventually eliminate their nuclear arsenals, in exchange for a pledge by other treaty states not to develop nuclear arms. The nonweapons states, meanwhile, are guaranteed access to peaceful nuclear technology.

That guarantee underlies the confrontation over Iran's uranium-enrichment program, which can produce both fuel for nuclear power plants and material for bombs. Washington contends Tehran has plans for such weapons, a charge Iran denies.

The German, French and British foreign ministers met with Iranian negotiators on Wednesday in Geneva in the latest round of long-running talks to get Iran to roll back its nuclear program in exchange for political and economic incentives.

The U.S. delegation here sought to have the conference focus heavily on Iran, and Main Committee II's proposal included a paragraph urging Tehran, among other things, to continue its current suspension of nuclear activities. But the Iranians objected to any mention in the text, since the situation is being handled in other forums, an Iranian delegate said privately.

Some delegations had hoped the U.N. meeting might jump-start an examination of ways to limit access to sensitive dual-use technology, such as enrichment equipment. But that looks unlikely.

Egypt also objected to Committee II's proposed document on the Middle East, where Arab nations have long sought a nuclear weapons-free zone, requiring Israel to dismantle its undeclared nuclear arsenal. The details of Egypt's objection were not immediately available.

Behind the closed doors of Main Committee I, meanwhile, the U.S. delegation objected to clauses in the text relating to weapons states' disarmament obligations, participants reported. Among other things, the proposal took a stand against "nuclear sharing," a term applicable to longstanding U.S. basing of nuclear weapons in European countries.

Many nuclear "have-nots" complain the weapons states are moving too slowly toward disarmament, and cite in particular Bush administration talk of "modernizing" the U.S. nuclear arsenal and its rejection of the 1996 treaty banning nuclear tests.

In reply, U.S. officials point to sharp reductions in strategic nuclear forces since the early 1990s. American actions "have established an enviable record of Article VI compliance," U.S. delegate Jackie Sanders told Committee I last week, referring to the treaty article on disarmament.