U.S. Secretary of State John Kerry has said that Washington would no longer insist that Iran fully disclose its past nuclear activities as part of a nuclear pact with Tehran.
Kerry said that in negotiations with Iran and five other world powers, the United States is no longer demanding that Iran answer queries made by the UN's International Atomic Energy Agency about past activities because the United States already knows exactly what Tehran has done.
"We're not fixated on Iran specifically accounting for what they did at one point in time or another," Kerry said, speaking by teleconference from Boston. "We know what they did. We have no doubt. We have absolute knowledge with respect to the certain military activities they were engaged in."
Critics of the emerging Iran deal have focused significantly on the issue of Iran's past military work. They insist Iran must not only "come clean" on such activity for transparency's sake, as U.S. administrations have long demanded, but that compliance with any accord can only be measured if Tehran provides a complete accounting of all its previous nuclear efforts.
Critics contend that without a full accounting from Tehran, the world won't have a full script of everything it needs to verify in the future.
Moreover, by dropping previous U.S. demands, the negotiators are likely to fuel accusations from Israel and other critics that the administration is stepping up concessions to Tehran as its self-imposed June 30 deadline for sealing a deal approaches.
But Kerry said the past is past, and the nuclear deal will be focused on preventing Tehran in the future from engaging in activities that could lead to its acquisition of a nuclear bomb, rather than any previous such activities.
"What we're concerned about is going forward," Kerry said. "It's critical to us to know that going forward, those activities have been stopped, and that we can account for that in a legitimate way."
But after reaching an interim accord with Iran in November 2013, the Obama administration said a comprehensive final deal "would include resolution of questions concerning the possible military dimension of Iran's nuclear program."
So far, the UN agency has been unable to resolve all of its questions about Iran's past military-related activities.
Much of Iran's alleged work on warheads, delivery systems, and detonators predates 2003, when Iran's nuclear activity first came to light. But Western intelligence agencies say they don't know the extent of Iran's activities or if Iran persisted in its covert efforts.
The UN agency's investigation has been foiled for more than a decade by Iranian refusals to allow monitors to visit suspicious sites or interview individuals allegedly involved in secret weapons development.
Tehran says the agency's evidence about past weapons-related activities is fabricated and insists its nuclear program is peaceful.
With reporting by Reuters and AP