Homes to be built on green belt double in a single year despite claims it would only be threatened in 'exceptional circumstances' At least 150,000 homes are planned on greenbelt land Over 1,000 acres will be used for railways, offices and warehouses The number of homes planned for the green belt has almost doubled in a year - despite ministers" claims it would only be threatened in "exceptional circumstances." Permission was given for more than 150,000 properties to be built on protected land, including some of the most scenic areas of the countryside, a report out yesterday showed. In addition, over 1,000 acres will be lost to office blocks, warehouses and the High Speed 2 rail link, according to the Campaign to Protect Rural England. Unprotected: At least 150,00 homes and over 1,000 acres will be built on anf flooded with private homes, offices and the HS2 speed rail link Protesters blame the increased threat level on government reforms to the planning system, which tells councils they should make a "presumption in favour of sustainable development." Proposed schemes include 46,000 homes and 607 acres of warehouses across Yorkshire, swallowing up much of the countryside surrounding Leeds, York and Calderdale. Up to 30,000 homes will be built as part of a development around Birmingham airport and 10,000 at sites across the South West close to Bristol, Bath, Cheltenham and Gloucester. The CPRE said it has "serious concerns" about the plans, and whether the pledge to build on the green belt only in "exceptional circumstances," contained in new planning guidance to councils two years ago, was being implemented. Sold: Green belt land for sale, such as this in Potter's Bar will see a large part of Britain's designated green belt land, introduced in the 60s, destroyed. Its figures reveal that permission was granted for 150,464 homes on green belt land in the past year, compared with 81,000 in the 12 months before that - a rise of 84 per cent. Just over 12 per cent of England has been designated as green belt land, a status introduced in the 1950s to protect the countryside around major towns and cities from urban sprawl. Labour has put a £50billion budget limit on the High Speed 2 (HS2) rail line and threatened to withdraw backing if costs rise any further. Transport spokesman Maria Eagle supports the plan to run 225mph trains from London to Birmingham - and later to Leeds and Manchester - but says there are "red lines" for her party. Her warning comes amid fears of a £30billion budget overrun. She said in an interview: "I am not willing to see this project start draining money from other vital rail projects - it's got to be delivered within the current budget. Nobody who is delivering it should be under any illusions that I will allow it to go up and up. That would put our commitment to it at risk. It shouldn't be going up above that £50billion cap. The line's budget was £30billion when given the go-ahead in 2010 but that has now risen to £42.6billion, and Treasury insiders are reportedly working on £73billion. Miss Eagle also called for HS2"s management to be replaced by "more experienced experts." Shadow chancellor Ed Balls has already expressed concern about HS2 while former Labour ministers Alistair Darling, Lord Mandelson and Lord Prescott are opposed. But ministers are believed to be divided over its future, with Communities Secretary Eric Pickles keen on preservation, and Chancellor George Osborne and Planning Minister Nick Boles saying it should not be immune from development. Shaun Spiers, chief executive of the CPRE said: "The green belt is hard to defend at the best of times, given the development pressures it faces. The job becomes almost impossible when powerful ministers such as the Chancellor and Nick Boles give out signals that it is up for grabs and that the need for growth trumps all other considerations. Mr Boles said earlier this year that an area the size of London must be built on to solve housing shortages and spoke of the Government's "moral" duty to prevent home ownership becoming the preserve of the rich. Councils have been told they must set land aside for 270,000 homes each year over the next five years and some have been ordered to review their green belt boundaries. The Government hopes that by doing so it can deal with the 2million people on housing waiting lists and spark a boom in the construction sector. But the move has been unpopular with Conservative backbenchers, and 20 Tory MPs have now joined an all-party group set up last month to oppose green belt development. Health Minister Anna Soubry has written to Mr Boles saying local authorities had "no alternative but to agree development on green belt land." The CPRE says former industrial - or brownfield - land could provide for 1.5million new homes.