People queue outside a food bank in Oldham. The borough volunteered to be a pilot area for universal credit, but the new system has left many residents struggling Andrew McCaren for The Times

Theresa May is warned by senior Tories today to end the benefit freeze for seven million people or see her party suffer at the next election.

The freeze, introduced by George Osborne in 2015, means a real-terms cut in income for millions of people and is due to continue until April 2020.

Five former cabinet ministers, including Justine Greening and David Davis, are leading the call for benefits to be raised now, in line with inflation.

The £1.4 billion move is also backed by Nicky Morgan, chairwoman of the Treasury select committee, the former work and pensions secretary Iain Duncan Smith and the former universities minister Lord Willetts. Another Tory MP, Heidi Allen, said that the freeze no longer made moral sense.

Their call comes…