Mitchell the first name revealed

Media playback is unsupported on your device
Media captionNick Robinson reports on the reshuffle

LATEST NEWS: I can confirm that Andrew Mitchell will become the new government chief whip in Tuesday's reshuffle.

He will replace Patrick McLoughlin, who will get a new job in government - as yet unknown.

I'm told that Mr Mitchell, who was International Development Secretary, has been involved in drawing up a plan for widespread change which will involve many in the middle ranks of the cabinet as well as many in more junior ranks.

Those in the top posts - the deputy prime minister, chancellor, foreign secretary, defence secretary, home secretary and business secretary will stay in their posts but many others may move or leave the government altogether.

10:05 GMT:

Not much work will be done in Whitehall today.

Ministers will be wondering whether they'll soon be clearing their desks. Civil servants will be gossiping about who might become their new boss. Backbenchers will be hoping that the call they've long dreamt of will come and come soon.

David Cameron's first reshuffle* looks set to happen on Tuesday. It looks likely to be more widespread than expected before the summer.

That means that whilst the cabinet's top three - Clegg, Osborne and Hague - will know that they will stay in their posts and whilst I'd be very surprised if Theresa May did not stay at the Home Office and Michael Gove remain at Education few, if any, other cabinet ministers can be sure about their futures.

So, there could be changes in significant posts - for example, Health, Justice, Transport, Culture, Media and Sports, Environment, International Development are all in play.

Let me stress that I am not predicting changes in any of those departments. Anyone who tells you they know what will happen is a mug and for a good reason - reshuffles often go wrong.

The prime minister's top aides will spend today in front of a whiteboard in No 10 armed with marker pens and yellow post-it notes plotting possible moves, checks that need to be completed first, people who have to be squared, calls that have to be made.

Restless parties

They will know that plans for reshuffles, like wars, rarely survive first contact with the enemy who, in this case, are the unpredictable, egotistical and irascible folk who make up not one but two increasingly restless parliamentary parties.

I recall one Blair reshuffle when I received calls telling me that his plan to create a new Ministry of Justice was on and another call, a few minutes later, saying that it was off as aides sought to placate a furious Lord Chancellor.

In New Labour's first round of appointments the No 10 switchboard - normally so efficient at contacting anyone anywhere at any time - invited the Tory former minister Lord Hunt (as against his Labour namesake) to speak to the PM about becoming health minister.

In Harold Wilson's day it was only once one lucky man was in the study at No 10 that everyone realised that this was the wrong Mr Davies (or was it Jones or Smith, I can't recall). Wilson, a man who knew the vengeful power of disappointment, decided to give the man the job anyway.

That, you see, is the problem with reshuffles.

Politicians are people who believe that they are capable of high office whatever you, or I, or their peers might think. They are apt to argue about which post they deserve or even refuse to accept a move.

All prime ministers hope that their reshuffle will inject new energy, ideas and presentational panache into their government. The danger is, though, that they inject inexperience, ignorance and tension into government as new ministers take a year to master their brief and to work out how to get on with their new colleagues.

'Destroying hope'

Remember that the good working relations between Tories and Lib Dems in most ministries were rooted in the days following the Rose Garden romance.

On the backbenches. reshuffles can destroy hope and sever the last hold party managers have on their grumbling troops.

David Cameron won plaudits on all sides at Westminster and in Whitehall for arguing against the annual reshuffle ritual.

He will now be feeling the pressure of a new conventional wisdom - that his government is going nowhere, is divided and does not know how to stimulate economic growth (as summed up in yesterday's excoriating editorial in the Sunday Times).

All the more reason why today he would be wise to ask himself repeatedly - will this move make things better or might it actually make things worse?

* as against the one in, one out approach he made when David Laws, Chris Huhne and Liam Fox left the Cabinet.