Theresa May has been overwhelmingly backed by MPs to seek to delay Brexit to June 30, amid Tory warnings over the impact of holding European Parliament elections.
The Commons approved a Government motion on the extension request by 420 votes to 110, majority 310.
Those opposed to the plan included 97 Conservative rebels, with former Brexit secretaries David Davis and Dominic Raab among them, while a further two acted as tellers to enable the vote.
The Prime Minister was forced to bring forward the motion under legislation pushed by Labour former minister Yvette Cooper, as part of a parliamentary bid to prevent a no-deal Brexit on April 12 – although any extension is subject to the decision of the EU.
Solicitor General Robert Buckland told MPs they “must find a way to find a plan for the way forward” to leave the EU with a deal and outlined how the UK would be legally required to take part in European Parliament elections if it remains a member state on May 23.
But he suggested British MEPs may not have to take their seats even if they are elected – should Westminster agree a deal in the coming weeks.
Mr Buckland said: “The new European Parliament does not meet until early July and therefore it is important for us to distinguish the need to have elections and then the requirement for British MEPs to have to actually sit in the European Parliament if we are indeed to leave the European Union before early July.”
Conservative former leader Iain Duncan Smith said Mr Buckland had suggested the UK may fight the European elections then “not to allow its MEPs to take their seats”.
Mr Buckland replied: “I think we’re obliged to, as a matter of law, prepare for European elections but if we have left and exited the European Union by the end of June then we are no longer members, we’re third countries and therefore the requirement to take our seats in the European Parliament would have ended.”
Conservative former attorney general Dominic Grieve said the UK cannot “go on lurching from one cliff-edge crisis to another” and outlined his desire for a longer extension to allow MPs to “make some decisions without the pressures”.
But Conservative former minister Tim Loughton, making an appeal to French president Emmanuel Macron and German chancellor Angela Merkel, said: “Please, put us out of our misery now, as this House and this Government appear incapable of doing.
“At tomorrow’s EU Council, please vote against any further extensions to Article 50 and oblige the UK to leave the EU on Friday on WTO terms, as you previously said you would only honour any application for an extension if there was a credible reason so to do. That credible reason does not not exist.”
Mr Loughton added: “If the EU elections go ahead, it is highly likely the UK will elect an army of Nigel Farage mini-mes, who I am afraid will wreak havoc with the European Parliament and wreck your calculations about the balance of power within the EU.”
Labour former minister Kate Hoey also said: “It does seem really humiliating for this country to have our Prime Minister going over to the European union to literally beg for an extension. What is this saying about our country?”
Tory MP Anne Main (St Albans) noted: “I think we are becoming a laughing stock, and I don’t know why anyone would turn up for any future referendum or even elections when they can not believe a word that goes on in here.”
For Labour, shadow Brexit minister Matthew Pennycook said the Government should be “mortified” that they have “to ask once again for this House’s approval to seek an extension to the Article 50 process”.
He said the fact one is required is a “damning indictment of the Government’s mishandling of the negotiations, and its failure to secure a deal that could command the confidence of the Commons”.
Mr Pennycook also confirmed his party “wholeheartedly supported the Government’s efforts” to secure an extension to Article 50, and said Labour expects them to agree to any “reasonable extension” beyond June 30.