Theresa May is likely to agree to a new parliamentary committee to help weed out excessive use of Henry VIII powers after Brexit as she seeks to head off a rebellion, according to Tory MPs pushing for the change.
Several Conservative supporters of the idea told the Guardian they believe the prime minister will back down on the issue because she cannot risk losing a vote when the EU withdrawal bill returns to the House of Commons later this month.
The amendment, signed by 15 Conservative MPs along with a number of Labour colleagues, has a chance of passing because of May’s slim parliamentary majority of 13 aided by the DUP.
The purpose of the EU withdrawal bill is to transpose legislation from Brussels into British law to ensure a smooth exit process.
However, May is facing a rebellion over so-called Henry VIII powers that would allow ministers to tweak secondary legislation as it is transposed.
Dominic Grieve, the former attorney general who tabled the key amendment, told the procedure committee on Wednesday that the bill represented the “most extraordinary arrogation of powers” by the executive that he had seen during 20 years in parliament.
He said there needed to be an exceptional mechanism for dealing with secondary legislation, where MPs would sift through statutory instruments to decide whether they needed full parliamentary debate or not.
This would help stop legal challenges against secondary legislation arising out of the process of transposing EU law into British law, Grieve said.
“The purpose of this amendment is not to put a spanner in the works of carrying out Brexit. If we’re leaving, we have got to have a credible piece of legislation for carrying it out,” he said.
John Penrose, another Conservative supporter of the amendment who sits on the pro-Brexit European Reform Group (ERG), said: “The amendments are gathering support and adherence and people now understand why they are important and responsible.
“If these changes are made, we will ensure the bill delivers a working statute book on the day after we leave the EU whilst not derailing Brexit.”
A second area where the government may be forced into concessions include strictly narrowing down the circumstances in which Henry VIII powers can be used. A slightly smaller group of Conservatives and opposition MPs is pushing for an amendment to require the final deal with the EU to be approved by statute passed by parliament.
The government could potentially make concessions by giving verbal commitments in the Commons, laying its own amendments or accepting amendments put down by Conservative MPs.
Hundreds of amendments have been tabled to the EU withdrawal bill, which is likely to return to the Commons for more detailed scrutiny in the next fortnight.
Another amendment that could gain traction was laid on Wednesday by two leading Conservatives, who want to push the government to commit to allowing refugee children to reunite with their families under post-Brexit immigration law.
Nicky Morgan, the former education secretary and a prominent remain supporter, and the former children’s minister Tim Loughton, who backed leave, submitted a proposal to ensure child refugees have the same rights to be reunited with family members in the UK as they currently have under EU law.
It is understood that a number of Labour, Liberal Democrat and SNP MPs will pledge their support for the measure in the coming days.
The children’s charity Unicef UK has previously said vulnerable children could end up being permanently separated from their families unless the government specifically includes family reunification rights in post-Brexit immigration law.
Refugees have the right to be reunited with extended family members in the UK under the EU’s Dublin III regulation, but the UK’s own immigration law covers only children and their parents.
Campaigners have said the government should commit to widening its definition of family to allow refugee children to be reunited with siblings, grandparents, aunts and uncles. Morgan and Loughton’s amendment would ensure this happens.
Unicef UK’s deputy director, Lily Caprani, said the amendment was “a display of the political will” in favour of helping child refugees, and urged MPs to add their names to the amendment.
“The UK must urgently establish a lasting solution for unaccompanied children desperately needing to be reunited with their close family members in the UK,” she said. “Brexit must not lead to our nation doing less for the world’s most vulnerable children.”