The group also said in a separate statement that it had attacked Riyadh's King Khalid International Airport and a pumping station on Saudi Arabia's East-West Pipeline.
Iranian media reported on Thursday that four oil tankers were hit by explosions in the waterway vital for global shipping, adding that the vessels had ignored warnings.
The IAEA said it "does not know [the] Isfahan Fuel Enrichment Plant's exact location, status for safeguards purposes, or whether it contains nuclear material."
The Guards said the strike was in retaliation for what they described as an air attack on a telecommunications tower in Iran's southern Sirik county, in Hormozgan province.
The president claimed that the US controls the Persian Gulf and the Strait of Hormuz, and that the blockade it imposed on Iran is severely damaging its economy.
The Saudi-led military coalition fighting the Houthis said later on Thursday it had intercepted and destroyed two drones launched by the group.
Iranian state media claimed on Tuesday that the Islamic Revolutionary Guard Corps had carried out strikes destroying "enemy navigation systems" on Didamar island.
The campaign reflects a broader effort by Riyadh to increase international pressure on the group, which has been carrying out near-daily attacks on the kingdom in recent weeks.
Tankers are still facing attacks across the strait, despite a rebound in traffic and expectations of a de-escalation in the war between the United States and Iran.
Fujairah Police said the truck driver lost control of his vehicle shortly before midnight on Sheikh Khalifa bin Zayed Road, near the entrance to Fujairah.
"The chances of obtaining an agreement which the regime would respect, and which would ensure zero nuclear capabilities, is low in my view," Barnea said.
