Theresa May has signed a letter that will formally announce the UK's exit from the European Union. It will be hand-delivered by Britain's EU ambassador, Sir Tim Barrow, to the president of the European Council at 12.30pm today.
In a statement to MPs, May will promise to represent everyone in the United Kingdom in the forthcoming negotiations with the EU, including EU nationals who have made Britain their home.
“When I sit around the negotiating table in the months ahead, I will represent every person in the whole United Kingdom – young and old, rich and poor, city, town, country and all the villages and hamlets in between," the prime minister will say.
"And yes, those EU nationals who have made this country their home. It is my fierce determination to get the right deal for every single person in this country."
Last night May called German chancellor Angela Merkel, European Council president Donald Tusk, and European Commission president Jean-Claude Juncker to update them ahead of the letter.
A spokesperson for 10 Downing Street said: "In separate calls, they agreed that a strong EU was in everyone’s interests and that the UK would remain a close and committed ally.
“They also agreed on the importance of entering into negotiations in a constructive and positive spirit, and of ensuring a smooth and orderly exit process.
“The Chancellor, the European Council President, and the European Commission President thanked the Prime Minister for her calls."
Under Article 50, Britain and Europe have two years to reach an agreement, meaning the UK will leave on 29 March 2019 unless the deadline for negotiations is extended.
However, there will be little movement on the European side until the end of next month, when a meeting of 27 EU leaders, without the UK, will agree to give the European Commission a mandate to negotiate with the UK. The negotiation guidelines based on this mandate won't be seen until May.
In her speech to MPs, May will say that the triggering of Article 50 is a moment for the country to come together. "We all want to see a Britain that is stronger than it is today," she will say. "We all want a country that is fairer so that everyone has the chance to succeed.
"We all want a nation that is safe and secure for our children and grandchildren. We all want to live in a truly Global Britain that gets out and builds relationships with old friends and new allies around the world."
She will add that the government's plan for Britain includes "ambitions that unite us, so that we are no longer defined by the vote we cast, but by our determination to make a success of the result.
"We are one great union of people and nations with a proud history and a bright future.
"And, now that the decision has been made to leave the EU, it is time to come together."
Philip Hammond said it was an “exciting” time for the UK to negotiate a “deep and special” relationship with the EU.
The chancellor, speaking to the BBC’s Today programme ahead of a cabinet meeting at 8.30am today, said: “This is a moment when we put the divisions of the past behind us and we look at the opportunities available to Britain in the future.”
Responding to questions from Nick Robinson about whether the Brexit process was a “leap in the dark”, Hammond claimed that “we are all on the same page”, and said all parties involved had the same agenda for exiting the EU.
Acknowledging that there had been a lot of discord in the country following the referendum result in June, Hammond said that over the past nine months, “people have started to think rationally and sensibly about the importance of the relationships between Britain and the European Union."
He maintained that the “overwhelming” majority of those negotiating with the UK in Europe wished for a “constructive” and “pragmatic” agreement that would result in “a relationship that will strengthen the UK, and the European Union”.
Hammond refused to be drawn on what might happen should there be "no deal", but did acknowledge there would be consequences because of the UK's decision to leave. "We understand that we can't cherry-pick, we can't have our cake and eat it," he said. "There will be certain consequences of that."
Quite apart from the plight of EU nationals, the talks are set to include a number of thorny issues that could take months to thrash out, including the UK's withdrawal from the single market and new customs and free trade arrangements with the EU; the eventual bill for Brexit, with some claiming Britain will have to pay up to £60 billion to leave; and the issue of sovereignty.
The Labour leader Jeremy Corbyn said: “Britain is going to change as a result [of Brexit]. The question is how." He added: "It will be a national failure of historic proportions if the prime minister comes back from Brussels without having secured protection for jobs and living standards.”
Keir Starmer, shadow Brexit minister, speaking early on Wednesday morning in front of parliament, said the real effort was now to hold the government to account under six “tough but clear” tests established by Labour.
“At their heart is a belief that although we can’t be members of the European Union, because of the referendum result, which we respect, we want an ongoing, collaborative partnership with our EU partners so that we have the proper trading arrangements. But more than that, there is so much going on in science, medicine, technology that we have done collaboratively and we don’t want to lose that,” he told the BBC, going on to also speak about the importance of security and intelligence cooperation with European agencies.
He added: “This is not about party politics, it is about what’s in the national interest for our country, because what is negotiated now will be relevant for at least a generation."
In response to questions on whether the Labour party was capable of holding the PM to account, Starmer said the party was “absolutely” up to the job, and batted off criticism of Corbyn.
Meanwhile, Nick Clegg, former deputy PM and Liberal Democrat leader, said the worst deal for the UK would be “no deal”.
“I think a no-deal outcome is the very worst outcome for the United Kingdom,” Clegg, who was an adamant Remainer, told the BBC.
“It would create unprecedented economic and legal uncertainty and really would jeopardize the British economy in quite a big way. So I think that is a huge risk no worth taking. But there's clearly a lot of people who are agitating for that to happen.”
Alan White is a news editor for BuzzFeed News and is based in London.
Contact Alan White at firstname.lastname@example.org.
Rose Troup Buchanan is a reporter for BuzzFeed News and is based in London.
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