At least 25 Tory MPs have spoken against the reforms and could vote with Labour to halt its introduction on October 18, after the party secured a vote on its rollout yesterday.
The government’s majority is 13, but relies on DUP MPs to maintain it.
Universal Credit — a combination of six benefits into a single payment — has been widely condemned as one in five claimants have had to wait more than six weeks to receive payments, plunging families into debt and rent arrears.
Evictions from rent arrears are also up 50 per cent due to the benefit overhaul.
Shadow work and pensions secretary Debbie Abrahams said: “The government is ignoring its own evidence and the concerns of its MPs to push ahead with its flawed Universal Credit programme.
“The social security system should work to prevent people from getting into debt, not to exacerbate it.
“The numerous problems with Universal Credit are not just administrative; the delays and cuts made by this government to the programme are all contributing to claimant debt.”
However many Tory rebels are calling for the scheme to be halted while operational flaws are sorted, and are not critical of the reforms themselves.
In the Commons on Wednesday, Labour leader Jeremy Corbyn urged Theresa May to “show some humanity” and scrap charges for people seeking advice from a Universal Credit telephone helpline.
He said that claimants who are already in financial difficulty are being forced to pay extortionate rates of up to 55p a minute.