After three years of bitter dispute, the prime minister’s deal has officially become law after clearing all parliamentary hurdles and receiving royal assent yesterday.
Earlier on Friday, European leaders signed the document in Brussels before it was transported to London by train.
Today, the Conservative politician uploaded a picture of himself smiling at the camera as he put pen to paper with two Union Jack flags in the background.
Writing on Twitter, he claimed his signature ‘heralded a new chapter in Britain’s history’.
He said: ‘Today I have signed the Withdrawal Agreement for the UK to leave the EU on January 31st, honouring the democratic mandate of the British people.
‘This signature heralds a new chapter in our nation’s history.’
Today I have signed the Withdrawal Agreement for the UK to leave the EU on January 31st, honouring the democratic mandate of the British people.
This signature heralds a new chapter in our nation’s history. pic.twitter.com/IaGTeeL2is
— Boris Johnson (@BorisJohnson) January 24, 2020
The moment was witnessed by EU and Foreign Office officials, including the PM’s Chief Negotiator David Frost, and Downing Street staff.
The Brexit bill still needs to be ratified by the EU but is expected to do so in time for the UK to leave as planned at 11pm on January 31.
The consent vote in the EU Parliament will take place on January 29.
Yesterday, Mr Johnson said the country would now ‘move forwards as one United Kingdom’.
He added: ‘At times it felt like we would never cross the Brexit finish line, but we’ve done it.
‘Now we can put the rancour and division of the past three years behind us and focus on delivering a bright, exciting future – with better hospitals and schools, safer streets and opportunity spread to every corner of our country.’
The bill had passed with a large majority in the House of Commons after the Tory’s victory in the December election.
It then went to the Lords, where Peers voted in favour of five amendments over two days of debate, leading Mr Johnson’s new government to its first parliamentary defeats.
The amendments included protecting the rights of refugee children to join their families post-Brexit. Ministers claimed they supported the principle of the Dubs amendment but argued that the Brexit bill was not the right way to do it.Meghan and Harry's bid to trademark Sussex Royal brand blocked by doctor
MPs were also defeated in the House of Lords on issues including EU workers’ right to have physical proof of their right to remain, the power of UK courts to diverge from EU law and the independence of the judiciary after the UK leaves the EU.
However, they were all overturned by the Commons to end the legislative tussle and send the bill to Queen Elizabeth for royal assent.
Once the UK leaves the EU, it will enter a transition period where it will follow the bloc’s rules and regulations while the terms of the future relationship are worked out.