Theresa May says she hopes Parliament can “come together” despite MPs’ differences over Brexit strategy.
Speaking at Prime Minister’s Questions, she said the government was “listening carefully” to those who were trying to change its flagship EU bill.
It comes after rebel MPs vowed to oppose Downing Street’s bid to enshrine the precise date of Brexit in law.
Several Tories brushed off criticism of their stance, including being labelled “mutineers” in a newspaper attack.
The Daily Telegraph’s front page was also condemned by a government minister, and later in the Commons Mrs May was asked to agree that part of MPs’ jobs was to scrutinise legislation.
She replied that while the UK was definitely leaving the EU, there was a “lively debate” going on with strong views being aired on both sides of the House.
“We are listening carefully to those who wish to improve the bill and I hope we can all come together to deliver on the decision that this country took,” she added.
The EU (Withdrawal) Bill is a key part of the government’s strategy for leaving the EU following last year’s referendum.
It aims to stop EU law from applying in the UK and avoid confusion on Brexit day – 29 March 2019 – by putting all existing EU law onto the UK statute book.
But there have been hundreds of suggestions by MPs to change the way it is worded and the government only has a majority with the help of the 10 Democratic Unionist MPs.
Ex-minister Stephen Hammond told BBC Radio 5 live the bill, which is currently being debated line-by-line by MPs, was “the most important constitutional thing we will do for 50 years” adding: “We might as well do it right.”
The government were “boxing themselves into a corner” in using the bill to specify the exact date and time of Brexit – 23:00 GMT on 29 March 2019 – he said, because the UK would be “hamstrung” if the negotiations needed to be extended at the last minute.
“It’s not about frustrating Brexit, it’s about getting the best economic deal for this country,” he added.
Mr Hammond said the Telegraph’s front page, picturing him and 14 colleagues with the headline “the Brexit mutineers”, was “silly” and criticised colleagues “lecturing” him on party loyalty.
Several more of those named hit back at the headline on Twitter.
Pro-EU ex-minister Anna Soubry, described it as a “blatant piece of bullying that goes to the very heart of democracy” while Bob Neill said he and his colleagues would “continue to work constructively for the best Brexit possible – that’s our duty – and what parliamentary democracy is all about.”
Also among the critics was Brexit Minister Steve Baker, who tweeted: “I regret any media attempts to divide our party.
“My Parliamentary colleagues have sincere suggestions to improve the Bill which we are working through and I respect them for that.”
MPs began eight days of detailed scrutiny of the bill on Tuesday evening, with ministers seeing off the first attempts to change the legislation.
The debate is continuing on Wednesday, with subjects being considered including employment rights, environmental protections after Brexit, the status of EU law and membership of the European Economic Area.
Speaking in the Commons, Labour’s Heidi Alexander made the case for the UK remaining in the EEA – which would give it full access to the single market but require it to accept freedom of movement rules.
Ministers, she argued, were seeking “backdoor authorisation” to leave the EEA at the same time as the EU – a sequence of events she described as an “economic suicide pact”.
Retaining EEA membership, she claimed, would give the UK more influence than a bespoke trade deal with the EU and would be a “simple and most surefire way… to stay close to the EU without actually being in it”.
But Solicitor General Robert Buckland said the public expected the UK to exit the “institutions of the EU” when they vote to leave last year and staying in the EEA was not compatible with that.
Speaking in the Commons for the first time since quitting as international development secretary last week, Priti Patel said MPs’ job was to deliver on the referendum result in as practical and open way as possible.
She said: “There are members tabling amendments and rightly so but what I don’t think we should listen to, really, is those who simply do not have the confidence in this House, in our democracy and also in our country going forward along with the suggestion we are incapable of governing ourselves.”
Meanwhile, German MEP Manfred Weber – a close ally of Angela Merkel – has said the next few days could be “decisive” in shaping the future direction of Brexit talks.
Speaking after meeting Theresa May in Downing Street, Mr Weber said he was more hopeful than before of progress but he said “concrete compromises” would be needed for the EU to agree to move on to the second phase of negotiations – focused on the two sides’ future relationship – in December.