Separately, in a phone call with the leader of the United Arab Emirates, Sheikh Mohammad bin Zayed, Mr. Pezeshkian signaled a willingness to return to talks, saying Iran was “ready to resolve issues at the negotiating table and within international frameworks,” according to an official readout of the call by the president’s office.

The president rebuked both countries for violating a truce in a conflict that has roiled the Middle East in recent days.

Meanwhile, nearly 400 kilograms, or 880 pounds, of uranium enriched to 60% purity is still publicly unaccounted for.