The US military says it has shot down four Iranian "one-way attack drones" launched toward the Strait of Hormuz, adding that the drones "posed an immediate threat to regional maritime traffic".

US forces "subsequently struck Iranian coastal surveillance radar sites in Goruk and on Qeshm Island to defend against further attacks", US Central Command (Centcom) said in a statement.

Iran has not publicly commented on the incident.

It comes several days after Washington and Tehran exchanged strikes, in an escalation that threatened a shaky ceasefire between the two countries.

One person was killed and more than 60 injured in Iranian drone strikes on Kuwait's international airport on Wednesday, local officials said.

Iran's Islamic Revolution Guard Corps (IRGC) denied responsibility for the airport strike, claiming the damage was caused by an error from a US missile interceptor.

Centcom said this was false and claimed Iran struck the airport in a "deliberate, calculated and unjustified attack".

The IRGC earlier said it had targeted US bases in the Gulf in retaliation for US strikes on an Iranian oil tanker and Qeshm Island.

The attacks happened as ceasefire negotiations between the US and Iran stalled, with a deal to end the war failing to advance.

The US and Israel launched wide-ranging strikes on Iran on 28 February, sparking conflict across the Middle East.

Iran responded by attacking Israel and US-allied states in the Gulf, and effectively closing the Strait of Hormuz, through which around 20% of the world's oil and liquefied natural gas travels. The move sent oil prices soaring globally.

Shortly after a ceasefire was agreed in early April, the US established a blockade of Iranian ports which President Donald Trump says will remain "in full force and effect until an agreement is reached, certified, and signed".