text: The prospect of a Labour government is knocking up to 10 per cent off the price of some of Britain's most expensive homes, it has been claimed. Wealthy buyers are demanding a lower 'Ed Miliband' price to compensate for any future mansion tax bills introduced by the Labour leader if he becomes Prime Minister. Estate agents in London are now said to be offering a higher 'Cameron price' and lower 'Miliband price' for the same property. Labour leader Ed Miliband, on the BBC's Andrew Marr show (left), has pledged to introduce a mansion tax on properties worth over £2million. The annual levy will hit his own home in north London (right) Mr Miliband has pledged to introduce an annual levy on homes worth more than £2million to raise money for the NHS. Under plans drawn up by shadow chancellor Ed Balls, homeowners with properties worth between £2million and £3million will be forced to pay £3,000 a year in mansion tax. Owners of homes worth more than £3million will have to pay even more. The Tories have dubbed the proposal the 'homes tax' and warned that families living in much more modest properties could be dragged into the levy. Mr Milliband himself has admitted that his North London home would be hit by his party's planned annual levy. David Cameron, on Sky's Murnaghan show this morning, has criticised Labour's proposed mansion tax as a 'home tax' A Labour government could see people's mortgage bills soar by £1,000 a year, George Osborne has claimed. The Chancellor warned warned that the prospect of Ed Miliband propped up by the SNP would lead to a 'clear and present danger' of rising interest rates. Predicting increases in mortgage rates, he said: 'A 1% rise in interest rates would hit the family with the average mortgage with an extra £1,000 bill a year. The price is paid by working people.' The Labour leader lives in a four-bedroom semi-detached house in Dartmouth Park valued at around £2.7million. But if Mr Miliband ever came to sell his home as Prime Minister he could be forced to lower the price to cover the costs of his own mansion tax. According to the Sunday Times, one buyer who is about to exchange contracts on a £15million property in St John's Wood, north London, has threatened to drop his offer to £13.5million if the deal is not completed before May 7 and Mr Miliband becomes Prime Minister. In Notting Hill, west London, a buyer of a property for sale just above £2million has said he will only pay that price only if David Cameron makes it back to Number 10. Miles Meacock, of Strutt & Parker, the estate agent, in Notting Hill, told the Sunday Times that the bidder who had trimmed £100,000 from their offer for a £2m property, wanted to be sure of permanently avoiding the burden of mansion tax. He said: 'If the Tories win, he will come back to the table. This is likely to be a phenomenon for the next two weeks.' According to the property website Rightmove 77 homes previously listed for sale above £2million have been reduced to below the 'mansion tax level' in the past six weeks. Ed Mead, an executive director at the London estate agent Douglas & Gordon, some sellers are so concerned about the mansion tax putting off potential buyers that they have told prospective buyers they will cover the full cost of it for a five-year Labour term. The Liberal Democrats have a similar mansion tax proposal. Nick Clegg wants to charge £2,000 a year on properties worth between £2million and £2.5million, rising to £3,500 for those worth between £2.5million and £3million, £5,000 for £3million to £4million and £9,000 for those worth up to £5million.
target: Estate agents are offering a 'Cameron price' and a lower 'Miliband price'
  Labour will introduce an annual levy on homes worth more than £2million .
  The prospect is alarming wealthy buyers who are demanding a discount .
  Some buyers are waiting until after the election to complete purchases .