A campaign to end a loophole which is estimated could cost councils a massive £250m in lost business rates revenue has been backed by senior politicians.

‘Box shifting' involves landlords exploiting a legal loophole in business rates relief by placing boxes in an empty commercial property to claim the space is occupied for six weeks.The boxes are then removed to claim three months of empty rates relief, with the cycle repeated. The practice adds little or no social value and causes councils to lose more than two-thirds of their rates income every time it happens.