The U.S. said that even full compliance would not be enough to ease international concerns over Tehran's possession of bomb-making technology. But despite that it urged Iran on Monday to cooperate with an investigation into past suspicious nuclear activities.
The comments by Gregory L. Schulte, chief U.S. delegate to the International Atomic Energy Agency, came as the IAEA's 35-nation board convened on the first day of a session that will focus on Iran's nuclear dossier.
Before the meeting, diplomats told The Associated Press that IAEA chief Mohamed ElBaradei's approach on Iran was leading to U.S. concerns that he has overstepped his authority - a view that Schulte appeared at pains to dispel by praising ElBaradei's attempts to pry answers out of Tehran.
"The United States ... strongly supports the IAEA's running effort to overcome Iran's refusal to cooperate fully and of course we will welcome any progress about resolving troubling questions about Iran's past nuclear activities," Schulte told reporters.
But even if Iran does give quick and thorough answers to IAEA questions on former programs that could be linked to a weapons program, "cooperation that gives Iran the wherewithal to build nuclear weapons is not enough," Schulte said.
Those comments were an allusion to U.S. concerns that Iran could exploit good will generated by signs it is cooperating on some issues to weaken concerns about its refusal to suspend uranium enrichment, as demanded by the U.N. Security Council.
ElBaradei called Tehran's defiance of the Security Council on enrichment "regrettable." And while noting that Iran has provided "additional information and access needed to resolve a number of long-standing issues," he said questions remained unanswered on other topics important to his agency's investigation. Also key, he said, was restoring and expanding his agency's access to encompass rights to search for possible hidden nuclear work that Iran may not have made public.
Before the meeting, diplomats linked to the International Atomic Energy Agency suggested that U.S. disenchantment with IAEA chief ElBaradei was at its highest since early 2005. That was when Washington actively considered pushing for his ouster because it considered him too soft on Iran and a drag on attempts to refer the Islamic republic to the U.N. Security Council - something that finally happened last year.
U.S. displeasure was again aroused this year, when ElBaradei suggested it was too late to expect Iran to scrap its uranium enrichment program, then signed a deal with Tehran committing the Iranians to end years of stonewalling and answer questions about more than two decades of nuclear activities - most of it secret, and some of it with possible links to a weapons program.
The U.S. suspects that Iran is exploiting the plan as a smoke screen to deflect attention from its continued defiance of a Security Council ban on enrichment, a potential pathway to nuclear arms.
The diplomats said Washington - and most other Western board members - also feel that ElBaradei overstepped his authority by agreeing to such a deal without consulting the IAEA board.
But publicly, Washington and other nations backing new U.N. sanctions against Tehran have toned down initial criticism over the pact because they have realized that opposition could backfire.
A diplomat said opposition could leave the impression that the U.S., France and Britain, the most vocal backers of new U.N. sanctions, did not care about resolving the issue that had sent Iran's nuclear file to the Security Council in the first place - its refusal to cooperate in dispelling suspicions about past nuclear activities.
Behind the scenes, however, U.S. opposition appeared to be continuing.
One of the diplomats said Washington had sent diplomatic notes to the other 34 board members asking them specifically not to "take note" of the action plan, so as not to give the impression that they were attaching significance to it.
Hitting back, ElBaradei said Friday that the action plan was "a working document between the secretariat and Iran" that the board has no business getting involved in.
Former U.N. nuclear inspector David Albright, said, however, that "because of the political sensitivity of the issue the board should have been consulted."
"I think what the U.S. is objecting to is that ElBaradei is trying to use the IAEA to do international diplomacy," he said. "ElBaradei doesn't have that mandate."