U.S. and Iranian forces have exchanged heavy missile and drone assaults, with Tehran targeting U.S. facilities in states across the Gulf ​on Sunday and saying it had again closed the vital Strait of Hormuz.

The renewed violence casts further doubt on the future of an interim U.S.-Iranian agreement signed last month that aimed to ‌reopen the strait and end the war after a further 60 days of negotiations.

The strikes were the latest in a cycle of attacks and counter-attacks as Iran seeks to assert control over shipping through the Strait of Hormuz. However, the barrage marked an escalation in pace and range.

Iran’s strikes extended to Qatar, a mediator in ceasefire talks that had not come under attack since April. The United Arab Emirates, which had not been targeted since early May, said its air defenses had engaged missiles and drones from Iran.

The U.S. military began launching ​more strikes against Iran at 5 p.m. ET on Sunday, Central Command said in a statement on the social media platform X, “to continue degrading their ability to attack civilian mariners and commercial ships freely transiting ​the Strait of Hormuz.”