Gordon Brown is facing calls from across the political spectrum to clean up the Downing Street machine after spin doctor Damian McBride resigned in disgrace over a plot to smear David Cameron and other senior Tories.
The storm over the dirty tricks campaign — exposed after the leak of an email from Mr McBride — was a savage blow to the Prime Minister's efforts to regain the political initiative.
Government hopes that Mr McBride's rapid resignation would ease the pressure were dashed after a Minister faced questions over how much he knew over the planned plot.
Last night Mr Cameron demanded a personal apology from Mr Brown over the scheme to slur him, as well as the shadow Chancellor, George Osborne, and his wife Frances.
Mr McBride — one of the Prime Minister's most trusted lieutenants — suggested false stories could be posted on a new website suggesting the Tory leader had an “embarrassing illness”, that pictures existed of Mr Osborne in women's underwear and that Mrs Osborne was “emotionally fragile”.
A spokeswoman for the Tory leader said: “David is absolutely furious and thinks that Gordon Brown should give an absolute guarantee that nothing like this will ever happen again.”
As Labour MPs also demanded an inquiry into who was involved in the scheme discussed in the exchange of emails between Mr McBride and Labour blogger Derek Draper, the party headquarters mounted a desperate damage limitation exercise.
They stressed Mr McBride had done the right thing by stepping down and distanced themselves from Mr Draper, portraying him as semi-detached from the party. They insisted that no-one else was involved, but Tory sources questioned the role of Cabinet Office Minister Tom Watson who was named in passing in one email.
Last night Mr Watson strongly denied being involved in the discussions between Mr McBride and Mr Draper on setting up an “attack blog” called Red Rag that would have spread unfounded gossip about senior Tories.
Mr McBride sent the emails from his Downing Street email account to Mr Draper, who runs the LabourList website, in January and copied in Charlie Whelan, a previous spin doctor to Mr Brown and now a union press officer. He admitted the messages contained a “bit of poetic licence”, but insisted the campaign would put the “fear of God” into the Tories.
Mr Draper responded: “Absolutely, totally brilliant, Damian. I'll think about timing and sort out the technology this week so we can go as soon as possible.”
After the emails fell into the hands of right-wing blogger Paul Staines, Mr McBride resigned on Saturday afternoon over the “juvenile and inappropriate” messages.
Mr Brown rushed out a strongly-worded statement insisting there was “no place in politics for the dissemination or publication of material of this kind”. He said the pair were right to decide not to publish the smears.
But his attachment to Mr McBride, who was sidelined in the Downing Street spin operation six months ago on the demands of Cabinet Minister, will raise fresh questions over the Prime Minister's judgement.
Mr Watson said yesterday he knew nothing about the emails and was not involved in discussions to the Red Rag website. He added: “I do not in any way condone the content of the email conversation — indeed I regard it as completely inappropriate.”