The Budget - what to expect in the Chancellor's speech

The printing presses will be turned on in the next 24 hours as soon as George Osborne's third budget is finalised.

But at the rate we are going there will be nothing new for the Chancellor to announce on Wednesday.

Being a product of a coalition government, much of the negotiating for Budget 2012 has occurred in public rather than behind closed doors.

But we now have it seems a much clearer idea of what will be in it.

The most controversial decision - and yet the one that affects only a few hundred thousand people - is the top rate of tax for those earning more than £150,000.

After much debate and agonising on the part of the Lib Dems, they have granted the Chancellor his wish and he is likely to announce it will be cut from 50p to 45p in April 2013. He may also signal a further cut to 40p a year later.

For their part, the Lib Dems have to show they have secured in return a tax cut for the low paid and an alternative assault on the wealthy.

They have not it seems secured their "mansion tax", the levy on homes worth more than £2m, which has been pushed so hard by the Business Secretary Vince Cable. Nor is there expected to be a "tycoon tax" which Nick Clegg pushed in his speech to the Liberal Democrat Spring Conference in Gateshead.

The wealth taxes they want will come in the form of closing loopholes, like on stamp duty.

And for the low paid - they will celebrate a large rise in the personal allowance - the amount you can earn before you start paying income tax. The allowance is already going up to £8,100 this April - there is likely to be a big jump to £9,000 next year.

That would lift more people out of paying income tax altogether and cut the income tax paid by all 23 million basic rate tax payers and by many of those on the higher rate.

It also moves the government closer to the £10,000 target set by the Lib Dems. The Treasury is likely to reach it before the next election rather than by the next election as promised.

But expect no U-turn on the controversial Child Benefit cut. The change affect only the top 15% of earners (those on more than £43,000) but it has angered a number of Conservative MPs who represent constituencies in the South where incomes are higher. The Chancellor will instead announce a way to soften the blow.

The most politically dangerous part of the budget will be the 50p rate cut for the richest people in the country at a time of austerity and Labour will attempt to maximise the discomfort for the coalition.

But George Osborne has got his way and it seems he has concluded the closer we get to the next election the more difficult it will be to change it.

He will also publish data to show the tax was raising very small sums and was holding back economic growth.

A tough sell. But the government hopes they will take a short term hit in return for long term gain.