BRITAIN joined the US in ousting the Taliban in 2001 because it feared America would "nuke the sh-t" out of Afghanistan, the former British ambassador to Washington has reportedly said on a TV documentary.

In comments published in advance in the Daily Mirror tabloid today, Christopher Meyer said fear explained why Prime Minister Tony Blair chose to stand with US President George W. Bush in his decision to invade Afghanistan in the immediate aftermath of the September 11, 2001 terrorist attacks - to temper his aggressive battle plans.

"Blair's real concern was that there would be quote unquote 'a knee-jerk reaction' by the Americans ... they would go thundering off and nuke the shit out of the place without thinking straight," Mr Meyer reportedly told the documentary, according to the Mirror.

In other excerpts of the documentary, printed in The Observer newspaper yesterday, members of Mr Blair's inner circle said the Prime Minister agreed to commit troops to the March 2003 US-led invasion of Iraq despite believing that the US had failed to prepare adequately for post-war reconstruction.

Britain's Channel 4 will air the first part of The Rise and Fall of Tony Blair on Saturday.