Gordon Brown’s appointment of ministers critical of the Bush Administration and the Iraq war has triggered unease in Washington after the departure of its close ally, Tony Blair.

Although the new Prime Minister emphasises his belief in the importance of Britain’s relationship with President Bush and the US, he has also delivered what one Pentagon source described yesterday as “some conflicting signals”.

The same source said that “eyebrows had been raised” over the decision to give a senior ministerial job at the Foreign and Commonwealth Office to Lord Malloch-Brown, the former Deputy UN Secretary-General, who has attacked Mr Bush’s “megaphone diplomacy” and America’s attitude to multilateralism.

John Bolton, the former US Ambassador at the UN, with whom Lord Malloch-Brown clashed repeatedly, has already described the appointment as an “inauspicious” beginning to the new Government.

Concern was also expressed through diplomatic channels last week over a speech made in Washington by Margaret Beckett, the outgoing Foreign Secretary, in which she criticised the “sense of stagnation” surrounding disarmament efforts and called on the US to ratify an international treaty banning nuclear tests — which Mr Bush has consistently refused to do.

Her speech may have been regarded as that of an off-message voice on a valedictory visit to the US, but her officials said that it had been explicitly authorised by Mr Brown.

Mrs Beckett was subsequently replaced by David Miliband, who is known to harbour doubts over the Iraq war. Last year he intervened in a Cabinet meeting to question why Britain was not taking a stronger position against Israel’s military action in Lebanon.

The White House will have noted also the appointment last week of John Denham, who resigned from government over the Iraq war, and Harriet Harman, Labour’s new deputy leader, who has suggested that the party apologise for supporting the invasion.

Mr Brown, who had a carefully arranged “drop-by” meeting with Mr Bush and his national security adviser, Stephen Hadley, earlier this year, is expected to have more formal talks with the President before the end of the summer.

Downing Street indicated that the trip could be as early as next month. Sources in Washington have suggested that Mr Brown may prefer to delay until September when he could “draw the sting” of being seen with Mr Bush — a hugely unpopular figure in Britain — by combining the visit with the Clinton Foundation’s annual conference in New York and a meeting of the UN General Assembly.

Figures close to the Bush Administration say that they have been encouraged by the general tenor of Mr Brown’s remarks towards the US and that they understand his need to “play the domestic political game” by demonstrating a degree of independence. But even the limited and coded signals from Mr Brown in the past week are a significant departure from the attitude of Mr Blair, who maintained an intense embrace of the US foreign policy even through his darkest days in office.

Some analysts believe he may want to wait until after the next general elections, in both Britain and the US, before becoming more fully engaged in the US.

Although he is not expected to make any dramatic departure from existing policy, Mr Brown’s immediate priority is winning his own mandate.

Such a strategy, however, carries the risk that Britain will lose influence to other European powers, such as France and Germany, who seem keen to heal their Iraq rift with the US.

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