Edward Klein, the author whose books have been routinely dismissed by critics as blarney, is claiming in his new unauthorized biography of President Barack Obama that Bill Clinton routinely mocked him as an 'amateur' behind his back.

Clinton, the new books claims, pressed his wife Hillary to quit her job as secretary of state last summer and instead challenge Obama in the primaries.

'The country needs you!' the former president reportedly told his wife, strongly urging her to run in 2012 according to sensational accounts of the behind the scenes conversation included in Klein's new book.

The explosive title 'The Amateur' was taken directly from Bill Clinton’s estimation of the president, the author claims.

'Barack Obama,' Clinton reportedly said, 'is an amateur.'

Critics are already charging that Klein's claim is preposterous, given that the former president is actively campaigning for Obama’s re-election now.

In the book, which has been quoted by the rightward-leaning New York Post, Clinton reportedly insists he has 'no relationship' with Obama. In fact, Clinton observes, he was more consulted by his presidential successor, George W. Bush.

Obama, Bill Clinton seethes, 'doesn’t know how to be president' and is 'incompetent.'

But Hillary didn't share his enthusiasm. 'Why risk everything now?' she allegedly told her husband, mindful of her legacy as secretary of state.

'Because,' Bill replies dramatically in Klein's book, 'the country needs you! The country needs us!'

The witnesses to these sensational exchanges were not named in the report in the New York Post, but its explosive claims were refuted on Thursday by spokesmen for both the White House and the Clintons.

Bill Clinton’s spokesman Matt McKenna scoffed that the excerpts that had leaked to date were 'totally and completely false' and he called Klein 'a known liar.'

Phillipe Reines, a spokesman for the secretary of state, also brushed off the books dramatic claims and reminded the press that the secretary dismissed a previous book Klein had written about her called 'Truth About Hillary.'

'Nobody in their right mind would believe the nonsense in this one, especially since both Secretary Clinton and President Clinton have been loyal and supportive of the president at every turn,' said White House spokesman Eric Schultz, who then accused Klein of making up facts to sell books.

Former US president Bill ClintonRalph Alswang / Clinton Foundation