Alistair Darling is “very secure” in his job as Chancellor, Downing Street made plain last night as it was forced to deny claims that he is under threat.

The Times understands, however, that Mr Darling’s future has been questioned by some in No 10 who argue that in a time of economic turmoil the Government needs someone as Chancellor who is established as a strong, independent figure.

They accept that Mr Darling has had to bear the brunt of some mistakes, notably the 10p tax-rate abolition, that must be laid at the door of Mr Brown. But they argue that for all his steadfast loyalty to Mr Brown he is not the “big figure” that the country needs during troubled economic times.

Gordon Brown, however, is understood to have reassured Mr Darling yesterday that his job is safe.

And The Times has learnt that Mr Brown has asked Mr Darling and Jack Straw, the Justice Secretary, to share the job of taking charge of the Government when he is away in August.

Weeks of Westminster gossip suggesting tensions in the relations between No 10 and No 11 surfaced in BBC speculation yesterday that Mr Darling’s days at the Treasury might be numbered.

This emerged after The Times reported on Saturday that Mr Brown was preparing to unveil an “economic report” in the autumn setting out how the Government intended to tackle the economic storms facing it, and asking to be judged on its success or otherwise.

The BBC questioned yesterday whether if there was to be a new economic statement setting out the path forward for Britain it would also make sense to have a new Chancellor to deliver it. But Mr Brown’s spokesman, when asked about the BBC report, called it “complete nonsense”.

It also emerged that he had asked the Chancellor and Mr Straw to share the duties of “minding the shop” when he is away. Mr Brown hopes to take a proper holiday this year – last year he famously spent four hours in the West Country before returning to London because of the foot-and-mouth outbreak – and he will be in China for the last few days of the Olympic Games.

Mr Brown is said to be attracted to the idea of having a senior Cabinet minister on hand to take charge of events if they arise unexpectedly. It will be Mr Darling for part of the month and Mr Straw for the rest, A No 10 insider said: “If Gordon was really thinking of ditching Alistair this would be a strange way to go about it.”

Even so insiders are reconciled to speculation continuing unless Mr Brown himself states categorically that he will not move Mr Darling, a corner into which he may not wish to box himself.

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