American military officials have raised concerns over an Iranian Revolutionary Guard warship aiming a gun at a US military helicopter in the Strait of Hormuz. Speaking to Reuters yesterday, the officials described the incident as “unsafe and unprofessional.” Although it was also described as “provocative”, the officials pointed out that “at no time” did the helicopter crew feel threatened.

The incident is the latest in a series of similar actions by Iranian warships this year, but the first to be reported since Donald Trump won the US presidential election earlier this month. Trump, who is due to take office on 20 January, vowed during his campaign that if he was elected he would “shoot out of the water” any Iranian vessel that harassed the US Navy in the Gulf.

The officials, who spoke to Reuters on condition of anonymity, said that the incident took place when a US Navy MH-60 helicopter flew within half a mile (0.8 km) of two Iranian warships in international waters. One of the ships aimed a gun at the helicopter, they said.

In September, a US Navy coastal patrol vessel changed course when an Iranian fast-attack boat came within 100 yards (91 metres).