Furious PM 'kicked desk' over lost tax data

Gordon Brown was so angry when the Government lost child benefit records on 25 million people that he kicked over a Downing Street desk, according to a documentary.

The claim follows a spate of rumours that Mr Brown has had temper tantrums, been rude to secretaries and smashed mobile phones as Labour slumped to its lowest opinion poll ratings since records began.

A Dispatches programme for Channel 4, "Gordon Brown – where did it all go wrong?", on Monday gives a flavour of the hostile reviews the Prime Minister can expect as he prepares to mark his first anniversary in the job on 27 June.

One of the turning points came when HM Revenue & Customs lost two discs with information on 7.25 million families last November. "When they told Gordon that the discs containing half the nation's details had been lost, he's supposed to have been so furious that he kicked the nearest desk," Sue Cameron, a Financial Times journalist, tells the show.

Last night, aides of Mr Brown said no one else would have been in the room when he was told about the lost discs in a call from the Chancellor, Alistair Darling. "There was no dramatic moment when we thought, 'Oh my God, we've lost the child benefit discs', so I don't know how anyone else can know his reaction," said one member of his inner circle. Mr Darling tells the show: "I was phoned at home on a Saturday morning and my initial reaction was ... probably unprintable."

Aides dismissed rumours he had broken three mobile phones by throwing them at a wall. They also denied a report he had insulted the group of secretaries who serve the Prime Minister.

One senior Labour figure told the show that Mr Brown was "playing fast and loose with the electorate" by going to Iraq to try to upstage the Conservative Party conference and then "stealing" the Tories' plans to cut inheritance tax.

The presenter Andrew Rawnsley claimed Mr Brown, not Mr Darling, was the architect of last October's pre-Budget report. The Chancellor admits in the show that he would have handled it differently.

Vince Cable, the Liberal Democrats' deputy leader, reveals he was congratulated by cabinet members after likening the Prime Minister to "Mr Bean".