Iran must clear up suspicions it worked on nukes as part of any deal with world powers

A U.S. envoy told Iran on Wednesday that it can expect substantial relief from sanctions choking its economy only if it clears up suspicions that it worked on nuclear arms. But Tehran said claims that it did so are "baseless."

The exchange reflected the obstacles remaining to a full nuclear agreement with Iran that would put to rest concerns that Tehran may be interested in atomic arms.

Iran and six world powers are now working on a comprehensive deal that highlights sanctions relief in exchange for an agreement by Tehran to substantially scale back nuclear programs that could be turned toward making a bomb.

On Wednesday, U.S. envoy Joseph Macmanus told the IAEA's 35-nation board that clearing up suspicions that Iran worked on nuclear arms "will be critical" to any final accord meant to give Tehran full final sanctions relief.

Tehran denies wanting — or working on — such weapons, and Iranian IAEA delegate Reza Najafi said Wednesday that his country does "not recognize" the allegations.

Iran is ready to work with the IAEA on its suspicions, but such "claims are baseless" he told reporters.