After Egyptian president Anwar Sadat’s historic visit to Jerusalem to address the Knesset, peace talks between Israel and Egypt became bogged down. President Jimmy Carter stepped in and invited the two leaders to Camp David.

They arrived on September 5, 1978, and, according the National Archive papers, remained behind the barbed wire fences that Mr Begin described later as “a concentration camp de luxe” with no news from outside and, more importantly, no leaks from within.

Mr Begin admitted later that he knew nothing at the time of Mr Sadat’s threat to pack his bags and walk out of the talks, even though their cabins were no more than 10 yards apart.

The story about President Sadat threatening to leave was revealed by Mr Begin during a press conference with British prime minister James Callaghan, whom Mr Begin insisted on briefing about the summit and broke his journey home to do so.

Mr Begin also revealed that President Carter worked until three or four o’clock in the morning “and was then up again at six” to try to broker a deal between the two countries.

Mr Begin said there was a “very intense atmosphere”, with President Carter spending up to three hours and sometimes longer in a session with the two men. After every round of talks the Israeli delegation went over what had been discussed.

Four days after Mr Begin flew home John — later Sir John — Mason, Britain’s ambassador to Israel, sent a telex to the Foreign Office about the reaction in Israel to the peace deal with Egypt.

It contained a chilling prophesy. Mr Mason wrote: “Optimists took simple view that Israel’s objective all through has been a bi-lateral deal with Egypt. Only Sadat’s assassination, they say, could get in the way of this brilliant project.”

On October 7, 1981, President Sadat was assassinated by members of the Muslim Brotherhood.