About 15 middle-ranking and junior ministers are expected to be sacked on Thursday when Tony Blair puts together the government team he wants to have in place at the next general election.
Sally Morgan, a senior Downing Street adviser, has been working on a plan to bring in a clutch of younger MPs, who gained their seats in the 1997 or 2001 elections.
The Prime Minister is also expected to make changes to his Cabinet - although at that level, ministers will change places with one another.
John Prescott, the Deputy Prime Minister, who celebrated his 65th birthday last week, is rumoured to be ready to have his workload reduced. While he is not expected to retire, allies say he is "relaxed" and "content the big things he wanted to do - transport strategy and regional assemblies - are in place".
He runs a huge department that covers local government, housing, social exclusion and other issues. Alan Milburn is expected to move into the Cabinet Office to take over some of Mr Prescott's duties, after nearly four years as Secretary of State for Health.
The new Health Secretary is likely to be be Patricia Hewitt, the Trade and Industry Secretary, who shares Mr Milburn's and Mr Blair's views on the urgency of NHS reform, and can be trusted to put up a stout defence of the controversial policy to allow some NHS hospitals to take on foundation status.
If Mr Blair moves Ms Hewitt, he will be appointing the fourth trade and industry secretary in six years. Two junior ministers in the same department, the energy minister, Brian Wilson, and the consumer affairs minister, Nigel Griffiths, may also be sacked.
Geoff Hoon, the Secretary of State for Defence, is known to want to move after four years in the job. He may take over from Ms Hewitt.
Another Westminster rumour is that John Reid, the Leader of the House of Commons, will swap jobs with the Chief Whip, Hilary Armstrong. This will mean thatMr Reid will not be heard on the Today programme again.
One change to the middle ranks that could prove highly controversial is that Mr Blair is believed to be intending to sack the environment minister, Michael Meacher, who is a popular figure in the party and well respected by environment pressure groups.
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