The Liberal Democrats are to unveil a rival Budget tomorrow in an unprecedented statement to Parliament which will signal the end of the Coalition . Danny Alexander , the Chief Secretary to the Treasury , will hold up a yellow budget box - mimicking the red leather case used by the Chancellor - before setting out what his party 's tax and spending priorities after the election . He will promise to make tax dodging as unacceptable as drink-driving , increase the personal tax allowance to £12,500 and targeting the wealthy instead of cutting spending . Danny Alexander will hold his yellow Budget box aloft tomorrow before delivering an unprecedented statement to the Commons . It is understood the unique statement from the Despatch Box had to be agreed with Commons Speaker John Bercow , and is likely to infuriate Labour for using government time to make a highly political speech . Nick Clegg has described the Budget as the 'last act of significant decision-making by this coalition Government ' . Chancellor George Osborne is using his Budget statement today to set out the official coalition government position for the last time before the election . But he has made clear that in a Conservative government he would eradicate the deficit through spending cuts alone , without tax rises . This would include £12billion of cuts from the welfare budget , including a ban on under-25s claiming housing benefit , restricting child benefit to three children and cutting the amount families can claim in handouts from £26,000 to £23,000 . But all the changes to benefits have been blocked by the Lib Dems , and are instead expected to be included in the Tory election manifesto when it is unveiled next month . On Saturday Mr Alexander unveiled his bizarre yellow leather briefcase which he held aloft in an echo of the Chancellor on the steps of Number 11 . It was later auctioned off to a Lib Dem activist for £1,500 . It is expected to make another appearance tomorrow , before Mr Alexander gives his statement to the Commons . The yellow box is designed to echo the red leather case used by George Osborne before travelling to the Commons to deliver his Budget today . Mr Alexander will rule out any extra increases to VAT , income tax or national insurance , but demand tax rises on the wealthy . He will use official Treasury figures to back up his call for the deficit to be eradicated through 70 per cent spending cuts and 30 per cent tax rises . A senior Lib Dem source said : We are going to set out what our spending plans will be for the next Parliament . 'There are big chunks that the Chancellor will say today which will be very much what the Tories ' plans will be . ' In a speech at the Lib Dem conference , Mr Alexander set out some of the measures which would be in a Lib Dem budget . He promised a crackdown on tax dodgers , saying it should become as socially unacceptable as drink-driving . In the wake of the HSBC scandal he said : 'As recent weeks have shown yet again , nothing upsets law-abiding taxpayers more than people who think they can evade paying the tax they owe . 'Paying the tax you owe is n't an optional extra - it 's a legal requirement . Quite rightly , benefit fiddling is a crime and a social taboo . For too long , tax evasion has been seen by the rich and privileged more like a sport than the crime it is . 'So in our future vision , there 'll be even more measures to crack down hard on the tax dodgers . ' He continued : ' I want to see those who aid , abet , facilitate or encourage tax evasion hit as hard with criminal and financial penalties as the tax evaders themselves . That will be in our manifesto too . ' Mr Alexander joined Mr Osborne and other Tory Treasury ministers outside Number 11 this morning . A Lib Dem budget would include the party 's flagship policy of raising the income tax personal allowance to £12,500 and would involve 'balancing the books fairly , not on the backs of the working people on low pay ' . He accused the Tories of wanting to 'cut for cut 's sake even after the books are balanced ' . ' A Conservative Party with no heart , but two minds . One to stay in Europe , the other to leave , ' he said . ' A Conservative Party that wants to balance the books solely on the backs of the most vulnerable in our society . 'The prospect of a Britain under a majority Conservative government is grim indeed . And have n't we all groaned when they use their soulless mantra - long-term economic plan . The truth is their long-term economic plan means long-term economic pain for millions of families . '
Chief Secretary to the treasury to make unprecedented statement to MPs . George also makes clear what he would like to do in Tory politics . tax Dems given rare chance to seek out rival candidates to the Commons . Will imposing tax raids on the wealthy and raising tax threshold to £ 12,500 .