Andy Burnham today paved the way for a new tax grab on Middle England.Millions of families could face soaring bills as the Labour leadership hopeful vowed to overhaul the council tax system and introduce a land value levy.Painting next month’s Makerfield by-election as an effective battle for No 10, Mr Burnham said it was ‘not justifiable’ that council tax was kept lower based on old valuations.He also demanded an annual duty on those holding assets, claiming land in the UK was ‘under-taxed’.The stance raises the prospect of Labour targeting huge numbers of homes whose values have risen sharply.Critics have warned such a move would hit families who have stretched themselves to buy a property and pensioners on fixed incomes. Landowners, such as farmers, would probably suffer too.And Mr Burnham came under fire from all quarters last night for trying to increase the tax burden – already at its highest level for decades under Labour – yet further.Conservative Party chairman Kevin Hollinrake said: ‘Andy Burnham cannot tell you what his council tax plan would cost, what would replace the current system or which households would foot the bill, because he does not know. Millions of families could face soaring bills as Andy Burnham vows to overhaul the council tax system