The prime minister has refused to confirm when he will announce details of his next Cabinet reshuffle, or whether Peter Mandelson will take a key European post.

At his monthly press conference in Number 10, Tony Blair brushed aside calls to confirm that it would happen this week.

"Much as I'd like to have a dialogue with you about the reshuffle, I'm not going to do it," he told reporters.

Despite the comments, much of Westminster is still waiting for a reshuffle of the government's ranks.

Mandelson, a former Cabinet minister, could also be appointed as Britain's next European commissioner.

Having survived a grilling at the hands of the press, it is the last major announcement expected from the prime minister before he begins a summer break.

Final touches

Ahead of his departure, Blair is thought to have been putting the finishing touches to his summer reshuffle.

Insiders suggest that most senior ministers are likely to remain in post.

But the most high profile scalps could be those of work and pensions secretary Andrew Smith and Labour chairman Ian McCartney.

More extensive changes could be forthcoming among middle ranking ministers.

Alan Johnson, widely praised for a robust performance during the knife-edge tuition fees debate, is almost certain to step up from his current role at education.

Ruth Kelly, financial secretary to the Treasury, and Douglas Alexander, currently at the Cabinet Office, are also being talked up for promotion.

Schools minister David Miliband may also be in line for a bigger portfolio.