US President Donald Trump has warned that Iran would “no longer exist” if the United States is forced to resume military action, following a fresh exchange of strikes that has further strained a fragile ceasefire between Washington and Tehran.

Iran said on Sunday it carried out a third consecutive day of retaliatory attacks against US targets after accusing Washington of violating a Pakistan-brokered truce intended to end the conflict that began in February.

The latest exchanges have raised concerns over the future of negotiations aimed at restoring stability and ensuring safe passage through the strategic Strait of Hormuz, a key route for global oil shipments.

Iran’s Revolutionary Guards said they had launched strikes on US military facilities at Ali al-Salem Air Base in Kuwait and the US Fifth Fleet base in Bahrain, claiming to have destroyed eight strategic targets.

The Guards also announced tighter controls on shipping through the Strait of Hormuz, warning that vessels violating Iranian directives would face stronger action.

Authorities in Bahrain confirmed that air raid sirens sounded twice on Sunday.

The renewed violence came after US Central Command said American forces struck multiple Iranian missile and drone storage sites, coastal radar installations, surveillance infrastructure, communication systems and air defence facilities.

According to the US military, the operation was carried out in response to an Iranian drone attack on the Panama-flagged oil tanker Kiku, which was transporting about two million barrels of crude oil.

Washington had launched similar strikes a day earlier, citing another Iranian attack on the commercial vessel Ever Lovely.

Reacting to the latest developments, Trump wrote on Truth Social that US aircraft had struck Iranian military targets for violating the ceasefire agreement.

“There may come a point when we are no longer able to be reasonable, and will be forced to militarily complete the job that we very successfully started. If that happens, the Islamic Republic of Iran will no longer exist!” he said.

Iran condemned the US strikes as a “blatant violation” of the interim ceasefire agreement.

The memorandum of understanding brokered by Pakistan in June committed both countries and their allies to refrain from military action against each other while allowing safe commercial navigation through the Strait of Hormuz for an initial 60-day period.

Meanwhile, tensions also escalated on Israel’s northern border after Hezbollah leader Naim Qassem rejected a US-backed agreement between Israel and Lebanon aimed at ending hostilities.

Israeli Prime Minister Benjamin Netanyahu described the agreement as a historic step that weakens Iran and Hezbollah, while insisting Israeli troops would remain in southern Lebanon until Hezbollah is disarmed.

Hezbollah, however, rejected the deal, describing it as a surrender of Lebanese sovereignty and calling instead for the full implementation of the wider US-Iran agreement.