Boris Johnson has sent a request to the EU for a delay to Brexit – but without his signature.
The request was accompanied by a second letter, signed by Mr Johnson, which says he believes that a delay would be a mistake.
The PM was required by law to ask the EU for an extension to the 31 October deadline after losing a Commons vote.
EU Council President Donald Tusk tweeted that he had received the extension request.
He did not provide details of its content, but added that he will now consult EU leaders “on how to react”.
Hours after losing a crunch vote in a historic Saturday session in the House of Commons, the prime minister ordered a senior diplomat to send an unsigned photocopy of the call by MPs set out in the so-called Benn Act, passed last month.
A senior Downing Street source said that the hard copy and email copy of the letter would be conveyed by Sir Tim Barrow, the UK’s representative in Brussels.
The two letters are also accompanied by a cover note from Sir Tim, explaining that the first letter complies with the law as agreed by Parliament.
The second letter from Mr Johnson – signed off this time – makes clear that he personally believes that a delay would be a mistake
It appeals to EU leaders to ask MPs to reconsider their decision, and vote for the deal the UK and EU have agreed without any further delays.
BBC Political Editor Laura Kuenssberg described the decision to send three documents as “controversial”, predicting “there will be a fight about whether Boris Johnson is trying to circumvent the court”.
She added: “This is heading straight for the court, and it may very quickly end up in the Supreme Court.”
Setback for PM
At the first Saturday sitting in the Commons for 37 years, MPs voted in favour of an amendment withholding approval of Mr Johnson’s Brexit deal until legislation to implement it is in place.
Tabled by Tory MP Sir Oliver Letwin, the amendment was intended to ensure that Mr Johnson would comply with the terms of the so-called Benn Act.
Under that Act, which required the PM to seek a Brexit extension, Mr Johnson had until 23:00 BST on Saturday to send a letter requesting an extension.
In a letter to MPs and peers on Saturday evening, he warned that the EU could reject “Parliament’s request for further delay” and added that he “will not negotiate a delay”.
“I will tell the EU what I have told the British public for my 88 days as prime minister: further delay is not a solution,” he said.
The Commons defeat marked a major setback for the PM, who has repeatedly insisted that the UK will leave at the end of the month come what may.
Mr Johnson told the Commons that he was not “daunted or dismayed” by the defeat and remained committed to taking Britain out by the end of the month on the basis of his “excellent deal”.
An EU source said that once Mr Tusk received the letter, he would start consulting EU leaders on how to react – which may take a few days, BBC Brussels reporter Adam Fleming reported.
Mr Johnson has vowed to bring in legislation on Monday to implement the deal he struck with Brussels this week.
MPs could also be given another vote on the deal then, if Commons Speaker John Bercow allows it.
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