David Cameron has told MPs there could be no second referendum if the UK votes to leave the EU on 23 June.
The Prime Minister addressed the Commons on Monday afternoon after striking a deal for a reformed relationship with Europe.
The idea of a second referendum was reportedly floated by Boris Johnson – who announced on Sunday he will vote Out – as a way of getting further concessions from the EU.
But Mr Cameron told MPs the June vote would be “final”.
He said: “Sadly, Mr Speaker, I have known a number of couples who have begun divorce proceedings but I do not know of any who have begun divorce proceedings in order to renew their marriage vows.”
Mr Cameron also seemed to make reference to the London Mayor”s motive in campaigning for Out amid speculation Mr Johnson has ambitions to be the next Prime Minister.
“I am not standing for re-election,” he said. “I have no other agenda than what is best for our country.”
The London Mayor restricted his contribution to a short question about how the Prime Minister”s EU deal would return sovereignty to the UK Parliament.
Mr Cameron responded: “It carves us forever out of ever closer union, it means that the ratchet of the European Court taking power away from this country cannot happen in future.”
The Prime Minister also warned it would take “years and years” for the UK to negotiate trade deals with Europe if the Out campaign wins.
Labour leader Jeremy Corbyn also put forward the case for In.
He told MPs: “We believe that the European Union has brought investment, jobs, and protection for workers, consumers and the environment, and we are convinced that a vote to remain is in the best interests of the people.”
A dissenting voice came from Employment Minister Priti Patel, one of seven MPs who attend Cabinet backing the Out campaign.
She said: “EU courts and politicians will still be in charge of our borders, our courts and our economy. The deal is not legally binding and can be ripped up by EU judges after our vote.
“Even if it did come into force it would change just 1% of the EU Treaties.”