Iran’s top nuclear official said Monday that his country might rethink its cooperation with the International Atomic Energy Agency if President Trump scrapped American participation in the 2015 agreement limiting Iranian nuclear activities.

The warning, from Ali Akbar Salehi, president of the Atomic Energy Organization of Iran, went beyond generic threats of unspecified Iranian reprisals if Mr. Trump reneges on the accord, reached with Iran and six world powers, including the United States.

The International Atomic Energy Agency is the nuclear nonproliferation monitoring arm of the United Nations. It polices Iran’s compliance with the accord, known as the Joint Comprehensive Plan of Action.

The agency’s ability to ensure that compliance, through a strict regimen of inspections, is considered critical to the survival of the accord, which is intended to ensure that Iran’s nuclear activities remain peaceful. The agency’s periodic reports since the accord took effect have shown that Iran is complying with its terms.