The US said it struck Iranian military sites at the weekend and Iran’s Revolutionary Guard said on Monday it had targeted a US base in response, the latest in a series of exchanges amid negotiations to end the three-month-old war.

The strikes on Iran’s Gulf coast were in response to “aggressive Iranian actions that included the shootdown of a US MQ-1 drone that was operating over international waters”, the US military’s central command (Centcom) said on X.

“US fighter aircraft swiftly responded by eliminating Iranian air defences, a ground control station and two one-way attack drones that posed clear threats to ships transiting regional waters,” Centcom said, adding it would continue to protect US assets and interests during the ongoing ceasefire.

Iran’s Islamic Revolutionary Guard Corps said on Monday it had targeted an air base used by the US for an attack on southern Iran, without identifying which base.

Air defences in Kuwait, where a major US base is located, were intercepting missile and drone attacks on Monday as sirens sounded across the country, the state news agency Kuna reported, without providing further details.

The US and Iran have sporadically exchanged strikes since their ceasefire took effect in early April as negotiations aimed at a more durable agreement drag on. A similar exchange occurred last Thursday and was described in similar terms by both sides.

The war launched by the US and Israel on 28 February has killed thousands of people – mainly in Iran and Lebanon – and caused global economic pain by pushing up energy prices due to Iran’s effective closure of the strait of Hormuz.

The US president, Donald Trump, has said one key aim in the war is to prevent Iran from developing a nuclear weapon with its highly enriched uranium. Tehran has consistently denied it has plans to do that.

Trump is under pressure to reopen the strait of Hormuz and get US fuel costs down ahead of the November congressional elections, as voters show increasing frustration over rising prices. At the same time, he faces a potential backlash from Iran hawks in his own party over any concessions to Tehran.

The two sides remain at odds on several other issues, such as Tehran’s demands for the lifting of sanctions and the release of tens of billions of dollars of Iranian oil revenues frozen in foreign banks.

Israel’s war in Lebanon with the Iran-backed Hezbollah militia is another major impediment. The Israeli prime minister, Benjamin Netanyahu, said on Sunday he had ordered troops to move further into Lebanon in the battle against the militant group.

The US secretary of state, Marco Rubio, spoke to both Netanyahu and the Lebanese president, Joseph Aoun, on the diplomatic negotiations between Israel and Lebanon and had proposed a plan to allow for “gradual de-escalation”, a US official said.