A former aide to Richard Nixon has said the president personally ordered the Watergate break-in which would ultimately lead to his downfall.
Magruder went to jail for his role in Watergate
Jeb Magruder said he heard a telephone call in which President Nixon approved the plan to break into Democratic headquarters at the Watergate hotel and bug the offices.
Previously, it had been thought that Nixon had only participated in the cover-up of the scandal.
Threatened by impeachment over the affair, Nixon resigned. Twenty-five people, including Mr Magruder who was Nixon's deputy re-election campaign director, were jailed for their involvement.
Mr Magruder said he had decided to disclose the new information in a US television documentary after suffering a heart attack.
He claims that he heard a telephone conversation in March 1972, three months before the break-in, between Nixon and his campaign manager and former attorney general, John Mitchell.
The two men discussed a plan by a member of the president's campaign team, Gordon Liddy, to bug the Democratic Party Chairman, Larry O'Brien.
Mr Magruder says he heard Nixon say : "John, we need to get the information on Larry O'Brien. And the only way we can do that is through Liddy's plan. And you need to do that".
John Dean, who was White House counsel under Nixon, said Mr Magruder's account was credible.
"It's not something that strikes me as something Nixon would never do," he said.
But Stanley Kutler, an expert in the Watergate scandal described it as "the dubious word of a dubious character".
Mr Magruder spent seven months in prison after being charged with perjury and conspiracy for his role in the affair.
Many of the other key players in the scandal, including Nixon and Mitchell, have died, making it hard to verify his account.