Iran on Tuesday accepted a compromise on the agenda of a 130-nation nuclear conference, clearing the way for the meeting to approve it and end six days of deadlock that threatened to doom the gathering to failure.

The issue stalling the meeting since it opened April 30 had been Tehran's refusal to accept a phrase calling for the "need for full compliance with" the Nuclear Nonproliferation Treaty.

Delegates said Tehran feared the language could lead to its becoming a target at the meeting because of its refusal to meet U.N. Security Council demands to cease uranium enrichment and other parts of its nuclear program that could be misused to make nuclear weapons.

A South African proposal accepted by consensus Tuesday will put an appended statement specifying that "all provisions" of the treaty must be fully observed — an allusion for the need for the United States and other nuclear weapons states to disarm.

With the Iranians showing no signs of compromise even after the South African proposal was floated Friday, a statement by Tehran's chief delegate, Ali Ashgar Soltanieh, that "my government can accept the proposal by South Africa" appeared to catch most delegations by surprise.

Subsequent approval was followed by brief, but relieved applause.

But the U.S. delegation criticized the Iranians, suggesting the delay had been unnecessary because it was clear all along that the phrase "full compliance" meant acceptance of all treaty provisions.

"It's been disappointing that as a result of Iranian obstruction of procedure, it has taken so long to get to the point of beginning substantive discussion," chief U.S. delegate Christopher A. Ford told reporters.

The phrase "all provisions" that Iran had been holding out for is a "restatement of the obvious," he added.

Iran argues it is entitled to enrich under the treaty provision giving all pact members the right to develop peaceful programs. But suspicions bred by nearly two decades of clandestine nuclear activities, including questionable black market acquisitions of equipment and blueprints that appear linked to weapons plans have led the U.N. Security Council to impose sanctions because of Tehran's refusal to mothball its enrichment program — which can generate energy or produce the fissile core of nuclear warheads.

The Nuclear Nonproliferation Treaty calls on nations to pledge not to pursue nuclear weapons in exchange for a commitment by five nuclear powers — the U.S., Russia, Britain, France and China — to move toward nuclear disarmament. India and Pakistan, known nuclear weapons states, remain outside the treaty, as does Israel, which is considered to have such arms but has not acknowledged it.