AMERICAN President Ronald Reagan apologised to an angry Margaret Thatcher following the surprise US invasion of Grenada, newly-released tapes show.

Mr Reagan ordered troops into the Caribbean island, part of the Commonwealth, in October 1983 after Prime Minister Maurice Bishop was overthrown and murdered.

The move infuriated Mrs Thatcher, who sent a response just after midnight on the day troops moved in, saying "This action will be seen as intervention by a Western country in the internal affairs of a small independent nation, however unattractive its regime."

In tapes released by the White House of a phone call responding to this message, Mr Reagan is heard speaking in a soft and apologetic tone as he seeks to appease his famously close ally.

Opening the conversation, he told the Prime Minister: "If I were there, Margaret, I'd throw my hat in the door before I came in."

She responds, saying: "There's no need to do that."

In a conversation lasting more than 10 minutes, Mr Reagan explained at length America had not given advance notice of the invasion because of fears a mole would leak sensitive information.

He added he had no "lack of confidence" in the UK's ability to keep a secret, adding: "It's at our end."

Mrs Thatcher seems to accept the apology and draws on her own experience from a year earlier in empathising with Reagan. She says: "I know about sensitivity, because of the Falklands."

She ended the call by saying she had to return to a "tricky" House of Commons debate. Mr Reagan answers: "All right. Go get 'em. Eat 'em alive."

The recordings from the White House Situation Room were released to author William Doyle following a Freedom of Information Act request he made in 1996.