PHILIP Hammond faces a “significant” backlash from Tory MPs unless he finds extra cash for welfare reforms, it has been claimed.

Thirty MPs are lobbying the Chancellor ahead of the Budget later this month after some claimants will be left worse off.

Tory MP Heidi Allen has revealed she had heard “positive noises” from Ministers after demands were lodged for extra cash to help families losing out.

She said that “significant numbers of colleagues on my side of the House are saying this isn’t right and are coming together to say the Chancellor needs to look at this again”.

Allen said the number of fellow Tories with concerns was “approaching 30 now” arguing for an extra £2 billion.

The architect of the new system, former work and pensions secretary Iain Duncan Smith, said an additional £2 billion must be pumped into UC to make it operate as planned.

Ms Allen told BBC Radio 4’s Today: “The two worst affected groups, and those that we should target financially, are single-parent families and second earners in families with children.

“To fix both of those would cost around £2 billion. I would argue that one of the ways of funding that - we have managed migration planned for next year, when we move all claimants across from the old benefits system, and the Government has put about £3 billion aside to protect those that would lose as a consequence of that.

“So if we boost the system before we get there, we can essentially save some of that £3 billion later down the line.”

But the Chancellor said he was considering temporary help for those in need.

Meanwehile, Lord Willetts, Executive Chair of the Resolution Foundation, said: “Big welfare reforms are always tough – millions of families will remember the traumas when tax credits were introduced.

“But the government has made the tough job of rolling out Universal Credit a lot harder by taking too long to fix design problems and by making severe cuts to the scheme.

“To get things back on track, the government needs to boost work allowances in Universal Credit and relax the rules for groups like the self-employed and families with childcare costs.

“That’s the right thing to do – and crucial to rescuing Universal Credit’s reputation.”