Tony Blair has been urged by his advisers to move Charles Clarke, Secretary of State for Education, to a different cabinet job because of a running disagreement over general election tactics.
Despite his reputation as a cabinet bruiser, Mr Clarke is being criticised for his reluctance to embroil himself in a political wrestling match with his Tory opponent, Tim Collins. Mr Clarke has argued that the way to win support among electors is by promoting government policies, set out earlier this month in the Department for Education's five-year strategy, rather than by attacking the Tories.
But aides working on preparations for the election, which Mr Blair is expected to call in less than a year, want it to be a battle over how to run schools and hospitals, rather than fight on issues such as asylum-seekers or Britain's future in Europe.
One leading Blairite said: "In an election, you either define your opponent, or you let your opponent define you. If we don't choose the key dividing lines, the Tories will. Charles's discursive style does cause some friction."
One idea raised in Downing Street is for Mr Clarke to go to Defence, on the assumption that Geoff Hoon will want to shift after nearly five years in the post.
The looming expectation of a reshuffle this week has produced the usual crop of rumours and speculation.
John Reid, the combative Secretary of State for Health, is said to be urging Mr Blair to seize the opportunity to end years of strife between Downing Street neighbours by demoting or sacking the Chancellor, Gordon Brown.
An aide dismissed the story as "tosh", adding: "John has repeatedly said that we have an excellent team, with the right people in the right jobs."
Peter Mandelson is said to be hopeful that his three years as a backbench MP will end, with a government job or an appointment as the next EU commissioner in Brussels.
For Mr Blair, the downside of appointing any of his MPs to the latter post would be a by-election which which Labour would be in danger of losing. Even before last week's defeat in Leicester South, the Secretary of State for Trade Patricia Hewitt had ruled herself out because of the risk that the Liberal Democrats would take her Leicester West seat.
Lord Razzall, the Liberal Democrat campaigns chief, told The Independent on Sunday: "If Mr Mandelson were to go to Brussels, we would have a very good chance of winning the by-election in Hartlepool. We certainly wouldn't need as big a swing as the one we got in Leicester."
Another way back for the former spin-doctor would be a new cabinet-level post which Mr Blair is considering creating, that of Minister for Europe, to see the Government through the planned referendum on the EU constitution and argue the case for the single currency.