<text>  Ed Milibands elections chief Lucy Powell, above, confirmed the party may use some investment borrowing to fund its manifesto if it wins . Labour yesterday admitted it will borrow billions more than the Tories as experts warned the partys plans would leave a 30billion black hole at the heart of the nations finances. Ed Milibands elections chief Lucy Powell confirmed the party may use some investment borrowing to fund its manifesto if it wins the election. And the Institute for Fiscal Studies said Labours plans would potentially leave Britain with a permanent budget deficit piling up massive debts for future generations. The think tanks director Paul Johnson said Labours proposals allowed it to maintain an overall deficit as high as 30billion by 2020 at a time when the Tories aim to be running a surplus of 7billion to pay off Britains debts. He told the BBC: It is clear Labour want to do quite a lot less in terms of the total deficit. They dont want to get rid of the deficit altogether, they are happy to borrow to invest. They would be happy with a deficit of 25-30billion, whereas the Conservatives dont want a deficit at all. Miss Powell later said she did not recognise the 30billion. But under pressure, she confirmed Labour would borrow to fund the Governments investment spending, which is forecast to be about that amount by 2020. We are going to balance the books for current expenditure by the end of the Parliament, she said. We may use some investment borrowing for much-needed investment but not for day-to-day spending. Those figures are other peoples figures. It depends on what the books are like. Tory Treasury minister Priti Patel said Miss Powell had let the cat out of the bag. She added: Labour have finally had it dragged out of them that theyd borrow more if Ed Miliband gets into Downing Street. Add in the fact that theyre refusing to admit which taxes theyd raise and youve got a recipe for total economic chaos. Miss Powell also clashed with BBC presenter Andrew Neil as he questioned Labours claims of an explosion in the use of zero hours contracts. She snapped at him: In the real world, Andrew where I live, OK, unlike where you live... Mr Neil hit back: Youve no idea where I live, just answer the question. Mr Miliband will use the launch of his partys business manifesto today to warn that Tory plans for a referendum on Europe could create instability for firms . Shadow chancellor Ed Balls told last Septembers Labour conference that in our manifesto there will be no proposals for any new spending paid for by additional borrowing. But the fine print of Labours pledges show it has left itself flexibility to borrow the Governments entire capital budget for spending on things such as roads, schools and railways.Shadow foreign secretary Douglas Alexander yesterday warned Labour may set out no more details of its tax and spending plans before the election. Critics point out its deficit reduction programme amounts to less than 1billion of cuts and the reintroduction of the 50p top tax rate, which experts warn may raise nothing. Challenged over Labours plans, Mr Alexander said: We have set out our programme. Miss Powell said Labour was very clear we can widen the tax base suggesting the party plans to drag more people into paying tax. Labour later insisted this meant getting more people into better paid jobs so they would pay more tax and receive fewer benefits. Shadow chancellor Ed Balls told last Septembers Labour conference that in our manifesto there will be no proposals for any new spending paid for by additional borrowing Mr Miliband will use the launch of his partys business manifesto today to warn that Tory plans for a referendum on Europe could create instability for firms. He is also expected to make a fresh attack on planned Tory cuts. But former Labour health secretary Alan Milburn said he had to reach beyond Labours usual supporters to have any hope of winning. Mr Milburn told LBC radio: Instead of going down to your core vote you have got to be reaching out to your non-core vote. Why? For a very pragmatic reason if you are going to form a majority government you cannot really do it with 32.8 per cent of the vote. Meanwhile, the Tories also came under fire over their plans for 12 billion in welfare cuts after Iain Duncan Smith indicated the proposals may not be made public before the election. The Work and Pensions Secretary added: When we are right and we are ready, we will talk about what we plan to do ... Voters know for certain that we are going to save that 12 billion. We may, we may not, decide that its relevant to put something out there about some of those changes. Labour activists were in mutiny last night over this shameful 5 mug boasting that the party would put controls on immigration. The red cup, for sale on the fundraising section of Labours website, is one of five carrying its key election pledges. Activists dubbed it the Farage mug, referring to the Ukip leader, and called on Labour to withdraw it and drop all plans to control migration. But the controversy led to a surge in sales. By last night almost 250 of the mugs had been sold compared to just six of the ones promoting Labours vow to create a strong economic foundation. Veteran left-winger Diane Abbott said: This shameful mug is an embarrassment. But the real problem is that immigration controls are one of our pledges at all. It comes after Labour was branded patronising for using a pink bus to attract women voters. A party spokesman defended the mugs, saying: Labour has five election pledges. This is one. 