Tensions have remained high between the two countries since US president Donald Trump withdrew from an international nuclear deal with Iran, which granted it sanctions relief in exchange for tight controls on the state’s nuclear programme.

Iran has shot down a US military drone using a surface-to-air missile, Iranian and American military officials said, amid an escalating row over alleged attacks on oil tankers in the Strait of Hormuz.

The two sides differed in their accounts of where it was at the time.

The US military described the incident as "an unprovoked attack on a US surveillance asset in international airspace", while Iran’s Revolutionary Guard said it had entered Iranian territory near the Kouhmobarak district in the south of the country.

The commander of the Revolutionary Guard said the downing of the drone had sent ”a clear message” to America.

In a speech delivered on state television, General Hossein Salami added that Iran does “not have any intention for war with any country, but we are ready for war.”

Two Iranian state media outlets carried statements that referred to a “spy” drone being destroyed on Thursday morning.

The US military, which initially declined to confirm reports of a downed drone, later said that an "RQ-4A Global Hawk" unmanned aircraft was hit by a surface-to-air- missile at 11.35pm on Wednesday evening.