Gordon Brown’s new strategic guru was accused of loose talk and naivety yesterday as months of tensions behind the scenes at No 10 spilt into public view.

Stephen Carter is being blamed for destabilising the position of Spencer Livermore, who has left after a decade in Mr Brown’s inner circle. The former PR boss is said to have briefed Labour MPs about his proposals to overhaul No 10’s machinery – plans that subsequently leaked, hastening Mr Livermore’s departure.

A friend of Mr Livermore told The Times that Mr Carter had been naive rather than malicious but said that he had been guilty of loose talk. The friend said that, although Mr Livermore had long intended to leave No 10, he had been upset by briefings against him.

Mr Brown, who tried to persuade him to stay, was forced as a result of the leaks to reassure personally his two most senior press spokesmen that their futures were safe.

Fears that Mr Carter is plotting a clean sweep of Mr Brown’s old guard were heightened by an apparently well-informed chart of the Downing Street operation published in PR Week. The chart relegates Damian McBride, the special adviser on press, and Michael Ellam, director of communications, to a marginal position while Mr Carter takes centre stage.

The Prime Minister is understood to have told both Mr McBride and Mr Ellam that their futures were safe in early February as it became obvious that Mr Carter was determined to bring in fresh blood. A minister said that Mr Brown had told them they were doing a good job and that talk of new staff was no reflection on them.

Friends of Mr Livermore insist that his departure as director of political strategy was agreed before Christmas and that its timing was dictated by his new job at Labour’s advertising agency Saatchi & Saatchi/Fallon. Insiders at No 10 do not deny, however, that Mr Carter’s arrival has been challenging for some both in Downing Street and in the Labour Party machine. One even compared it to Peter Mandelson’s arrival in 1985 as director of campaign and communications.

Like Mr Mandelson, Mr Carter is quickly establishing a reputation for ruthlessness. He was forced to deny reports last week that he was trying to reduce the influence of Ian Austin, Mr Brown’s parliamentary private secretary. Sources close to Mr Carter were quoted at the weekend pointing out that Mr Livermore bore some of the blame for the election speculation fiasco last autumn.

The tensions in No 10 have surfaced as Labour has been battered by a series of opinion polls showing it to be trailing the Conservatives heavily in the wake of last week’s Budget and the global financial turmoil.

With Ken Livingstone facing a serious challenge from Boris Johnson in the London mayoral contest, party strategists are braced for a tough spring and summer.

Labour MPs increasingly believe that Mr Brown will not call a general election until 2010, the fifth and last year of the parliament, because of the huge uncertainty over the economy.

The Cabinet met in political session yesterday, and is understood to have had a lengthy discussion about the state of political opinion. Strategists say that, although Labour’s internal polls show it to be behind the Tories, the worries about the world economic situation had added to voters’ concerns about their own prospects and that had shown up in the polls.

One minister said that there was no choice but to “take it on the chin” and try to convince the electorate that the Government could manage difficulties better than the Conservatives.

Talk of a purge at No 10 was being played down last night but senior allies did not deny that both Mr Brown and Mr Carter were being urged by several Cabinet ministers to do more to calm veterans’ fears.

“This has got to be about team work – it’s not one person doing everything,” a senior figure said.

New guard

Stephen Carter formerly chief executive of Brunswick, brought in at the new year to restore Gordon Brown’s fortunes after the autumn nonelection debacle. Admirers marvel at his clear-sightedness, detractors mock him for being politically gauche

David Mui, headhunted from the advertising giants WPP, to sharpen Labour’s message. Said to be a friend of Steve Hilton, David Cameron’s strategic guru

Nick Stace was formerly director of communications Which?. Has been asked to draw up a plan from now until the election

Old guard

Sue Nye Mr Brown’s longest-serving aide, part gatekeeper, part “body-person”, it is Nye who regulates access and warns the PM when he’s tucked his socks into his trousers. Again

Damian McBride Cambridge-educated former Revenue & Customs press officer, left Civil Service to take an overtly political role briefing journalists

Michael Ellam The Prime Minister’s official spokesman and director of communications. A career civil servant, Mr Ellam scrupulously avoids party political briefing

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