Giles Whitaker, deputy head of mission at the British Embassy in Tehran, was among several foreigners detained by Iran's Revolutionary Guards for alleged acts of spying, according to state TV.

A report said: "These spies were taking earth samples in Iran's central desert where the Revolutionary Guards' aerospace missile exercises were conducted."

The TV station showed footage of Mr Whitaker and his family in central Iran, where he appeared to be taking ground samples.

Iran's Fars news agency reported that Mr Whitaker, who was an army officer before a long career with the Foreign and Commonwealth Office, will be deported after apologising.

Also among those detained was the husband of Austria's cultural attaché in the country and a Polish university professor who had been visiting Iran as a tourist, the report said.