Updated

Momentum is building at a 35-nation conference to take Iran (search) to task for hindering a U.N. probe of its nuclear agenda.

Ahead of Monday's opening of the board of governors' meeting of the International Atomic Energy Agency (search), diplomats said Iran was seeking to soften the language of a draft resolution. The draft is laden with negative terms, "deploring" omissions and delays by Tehran in cooperating with the probe of the IAEA or noting them with "serious concern."

An Iran resolution will likely be presented during the meeting. The gathering will review an agency report that notes Iran's cooperation in granting IAEA inspectors access to sites but otherwise gives it low marks in eliminating concerns about activities that the United States and its allies say point to attempts to make nuclear weapons.

The two major IAEA concerns are contradictory, missing or withheld information on the scope of Iran's enrichment program and the source of enriched uranium found inside the country.

The latest agency report, written by IAEA head Mohamed ElBaradei (search), says Iran inquired about buying thousands of magnets for centrifuges on the black market — casting doubt on Iranian assertions that its centrifuge program was purely experimental and not geared toward full enrichment.

As for traces of enriched uranium, including minute amounts at weapons-grade levels, Tehran says they were inadvertently imported on purchases through the nuclear black market.

But IAEA investigators have not been able to fully test that claim because Pakistan — the main source of the equipment — has blocked access to its nuclear material, meaning the agency cannot match isotope samples to the traces found in Iran.

Iran long has rejected U.S. allegations its nuclear program is for military purposes. ElBaradei said last month his agency had not found proof to date of a concrete link between Iran's nuclear activities and its military program, but "it was premature to make a judgment."

Iran insists its uranium enrichment program — which could be used to make bombs, once it is fully operational — is geared solely to generating electricity.

Under pressure since the start of international scrutiny a year ago, Iran has already suspended uranium enrichment and stopped building centrifuges. It has also allowed IAEA inspections of its nuclear facilities without notice.

The draft resolution, written by France, Britain and Germany, urges Iran to ran halt operations of a plant it inaugurated in March that processes uranium into gas. The demand also calls for aborting plans to build a heavy water reactor.

But sounding a tough note, Foreign Minister Kamal Kharrazi insisted that Iran would not give up its development of the nuclear fuel cycle. Iran says it has achieved the full cycle, but is not now enriching uranium.

"We can't accept such an additional demand, which is contrary to our legal and legitimate rights," he said Saturday in Tehran.

Kharrazi also condemned the draft, as "unacceptable unless changes are made so that it can be acceptable to all parties."

One of the diplomats said small changes were made Friday to the draft, including introduction of a "time element" that nonetheless fell short of U.S. hopes for a deadline on Iran to come clean or a "trigger mechanism" that would allow additional pressure if Tehran failed to satisfy board demands within a given time.