A furious row erupted today between the Lib Dems and Conservatives over claims David Cameron is plotting to 'slash support for families'. Lib Dem minister Danny Alexander released details of what he claimed are secret plans drawn up in the last government to cut Child Benefit and Child Tax Credits. The Prime Minister 'flatly rejected' the plans, claiming they were drawn up by civil servants on the orders of Mr Alexander. But the Lib Dems hit back, claiming Mr Cameron himself had asked officials to examine ways to curb access to benefits. David Cameron, campaigning in Wetherby, West Yorkshire today, has hit back at claims the Tories have a secret plan to cut child benefit . Conservatives angrily denied the specific proposals set out in the document revealed by the Lib Dems but they remain under pressure to spell out how they will making savings from the benefits bill. According to Danny Alexander, the unimplemented Tory proposals included: . The clash is the worst row between the two former coalition partners and will raise serious doubts about whether they could work together again, if the Tories fall short of a majority. Conservatives angrily denied the specific proposals set out in the document revealed by Mr Alexander. But they remain under pressure to spell out how they will making savings from the benefits bill. Tory Chancellor George Osborne has promised to cut £12billion from the welfare bill after the election, but has repeatedly refused to say where the axe will fall. Lib Dem leader Nick Clegg expressed outrage that the Tories could not be 'bothered' to come clean about their plans. The Lib Dems have vowed to block the plan as the price of any future coalition deal after May 7. Mr Alexander, who served as Chief Secretary for the Treasury, has now released details of benefit cuts put to the Quad of senior ministers, which included him, Lib Dem leader Nick Clegg, Prime Minister David Cameron and Mr Osborne. He said he was lifting the lid on the internal coalition discussions because his former government colleagues were 'trying to con the British people by keeping their planned cuts secret until after the election'. Lib Dem leader Nick Clegg told LBC's Nick Ferrari that he backed Mr Alexander's decision to disclose details of confidential coalition discussions . Vince Cable has claimed the Tories have a 'nasty streak' as he warned workers had been hit hard by the coalition he served in. The Business Secretary claimed the Conservatives would resurrect plans to allow bosses to 'fire at will'. He told The Independent: 'They have an unfinished agenda. 'There is a very nasty streak [in the Conservative Party]. They are not all nasty as individuals. 'I have worked with them for five years. Some of them are perfectly decent, moderate people.' But he warned the Tories would 'chisel away' at workers' rights. The Lib Dems revealed that in June 2012, the Quad was sent a document called 'Welfare Reform Quad Summer Reading Pack' produced by officials working for Work and Pensions Secretary Iain Duncan Smith. Mr Alexander said the previously dropped plans - including limiting Child Benefit and Child Tax Credit to two children at a cost of £3,500 for a family of three - were a clear signal of where the axe would fall. But he was forced to admit that many of the claims set out in today's document had been made public - and rejected by the Tories - in the past. He told BBC Radio 4's Today programme: 'There are lots of ideas that have been doing the rounds for years, so I think it's not credible for the Conservatives to say they do not know what they're going to do. 'If they are proposing £12billion of welfare savings without knowing what they're going to do, that is highly reckless. 'Equally, if they do know what they want to do and they're not telling the British people, that is deceitful. 'And that does frustrate me because I think that this is one of the issues that in the last seven days of the election campaign people would expect the Conservatives to come clean about.' Mr Clegg  backed Mr Alexander's decision to disclose details of confidential coalition discussions saying the Conservatives needed to say where their planned benefits cuts would fall. 'I share Danny's intense frustration verging on anger that the Conservatives think it is okay a week before an election to say that they are going to take the equivalent of £1,500 off eight million of the most vulnerable families in this country and they can't even be bothered to spell out exactly what their plans involve,' he said on an LBC radio phone-in. But the Conservatives dismissed the claim as 'desperate stuff' from the Liberal Democrats and insisted the proposals were 'definitely not our policy'. Mr Osborne told BBC London: 'Well this is a three year old document of policy options that was commissioned by the chief secretary himself. 'We have not put into practice any of these options. We don't support them. We didn't support them. We don't support them in the future.' Labour leader Ed Miliband, pictured in Dewsbury today, said the future of child benefit and tax credits is 'on the ballot paper next week' David Cameron will today pledge to cut taxes for the young as he warns Labour would 'reach into your pay packet' by raising them. Young people have been the biggest winners from the increases in the personal allowance since 2010, according to new figures, with five million under-30s gaining an average of £70 a month each from being taken out of income tax. A further 500,000 will gain from the extension of the policy after the election. The announcement is part of a wider offer to young voters today. This includes a target to cut youth unemployment to the lowest level in the G7 group of nations. With just a week to go until polling stations open across the UK on May 7, Mr Cameron told the Guardian it was 'time to throw caution to the winds, let rip and tell people what you really think'. The Prime Minister - who has in recent days deployed a more energetic approach after criticism of a lacklustre pitch to the electorate - said: 'I think we will get there. But the reason it is taking time is, quite rightly, people want to have a good look and a good think.' Tory Culture Secretary Sajid Javid told Sky News: 'This is just a desperate attempt by the Lib Dems to try to move their position in the polls, but it's not going to work because these proposals were never proposed or supported by the Prime Minister or the Chancellor and they would never be supported by the Prime Minister or the Chancellor. 'Our principles are very clear when it comes to welfare: it is there to help people, especially to help people get back into work, but also to support the disabled, to support pensioners - and those principles will not change.' Mr Alexander's revelations came as The Times reported growing dissent in Lib Dem ranks over the possibility of entering a second power-sharing deal with the Conservatives if the General Election fails to produce a clear winner. Nick Clegg has based his campaign around the premise that his party would be a restraining influence on either of the main parties. But the newspaper said a number of - mostly unnamed - parliamentarians were increasingly hostile to the prospect of a Tory tie-up, which would have to be approved by a special party conference. Mr Alexander said: 'For five years I won battle after battle to stop the Tories veering off to the right with ideological cuts, and it's been worth it to get the economy back on track while ensuring a fairer society. 'The coalition has delivered savings in a fair way, but the Tories now want to balance the books off the backs of ordinary working families and the most vulnerable in society. 'The Tories have turned their backs on the plan delivered in coalition government. Instead they want to cut £1,500 for eight million households, singling out middle and low-income families to bear the burden - and asking nothing from the best off. 'It's clear from our time in government that the Tories' target will be slashing support for families. I'm lifting the lid on this now because the Conservatives are trying to con the British people by keeping their planned cuts secret until after the election. 'They now ask the British people to trust them when they make unfunded pledges on health and tax, yet won't tell us how they will cut welfare for millions of families to pay for their plans. They may give with one hand, but they will take away twice as much with the other. 'The Liberal Democrats will take a fairer approach, cutting less than the Conservatives and borrowing less than Labour, to deliver a stronger economy and fairer society with opportunity for everyone.' Labour leader Ed Miliband also seized on the revelation.Speaking ahead of an event in Yorkshire, he said: 'Today we've learnt that child benefit and tax credits are on the ballot paper next week. 'The Tories have drawn up plans to take thousands of pounds away from millions of families. 'The Tories' secret plan has been revealed. 'And they will put it into practice in just seven days' time if they get the chance. 'It's the final proof that working families can't afford five years of the Tories.‎' CONSERVATIVES . LABOUR . LIB DEMS . UKIP . GREENS .
Danny Alexander exposes 'secret' plans by Tories for £8billion welfare cuts . Accuses Conservatives a 'con' by keeping cuts secret until after election . Tories hit back and brand their former coalition partners 'desperate' Growing dissent in Lib Dem ranks over  a second coaliton with Tories . No income tax on earnings less than £12,500 . Cut £12billion from the welfare bill . Introduce a new law to ensure those working up to 30 hours a week on the minimum wage are never subject to income tax . Raise the 40p Income Tax threshold to £50,000 . Guarantee not to raise VAT, National Insurance contributions or Income Tax . Cap benefits at £23,000 a year . Increase the Inheritance Tax threshold for married couples and civil partners to £1million . Abolish the Bedroom Tax . Re-introduce the 50p top rate of tax on those earning more than £150,000 . Guarantee not to increase the basic 20p or higher 40p Income Tax rate . Guarantee not to raise VAT, National Insurance contributions or Income Tax . Introduce a new 10p tax rate for the first £1,000 of taxable income . Abolish 'non dom' status . Cut and then freeze business rates . Increase corporation tax by 1 per cent . Increase working tax credits . Halt and review Universal Credit . No income tax on earnings less than £12,500 . Consider raising the employee National Insurance threshold to the Income Tax threshold . 'Limit' welfare reductions . Introduce a mansion tax on properties worth over £2million . Cut £3billion from the welfare bill . Cap increases in working-age benefits to 1 per cent until 2017/18 (not including disability or parental leave benefits) Increase benefits in line with inflation once the deficit has been cut . No income tax on earnings less than £13,000 . Raise the threshold for paying 40 per cent income tax to £55,000 . Abolish inheritance tax . Introduce a new tax rate of 30 per cent on incomes ranging between £43,500 and £55,000 . Remove VAT completely from repairs to listed buildings . Reduce the annual cap on benefits . Scrap the 'bedroom tax' Increase taxes by £200billion by 2019 . Introduce a wealth tax of 2 per cent on people worth £3m or more . Bring in a new 60 per cent income tax rate on earnings over £150,000 . Double child benefit .