Boris Johnson’s Brexit deal has become law after passing all parliamentary stages and being approved by the Queen.
Some MPs cheered as deputy Commons speaker Nigel Evans confirmed the European Union (Withdrawal Agreement) Act had received royal assent in a short announcement to the chamber.
It paves the way for Britain’s legal departure from the EU at 11pm on January 31, although it will then be in a standstill transition arrangement with Brussels until the end of 2020.
The Prime Minister was able to push his withdrawal agreement through parliament with ease after winning a majority of 80 in last month’s general election.
However, all three devolved parliaments have formally refused to consent to the legislation – unprecedented in the history of devolution.
The UK Government has said, under convention, it would not normally legislate without the approval of the devolved legislatures, but stated the “singular and exceptional” nature of Brexit justified proceeding against their wishes.
Responding to the news of royal assent, the SNP’s Westminster leader Ian Blackford said: “This is a constitutional crisis.”
“We are faced with a situation which is completely unprecedented when the governments in Edinburgh, Belfast and in Cardiff have not given consent to this Act of Parliament.
“That completely contravenes the devolution settlement that made it clear that the consent of the devolved administrations had to be given in Bills of Parliament that become Acts of Parliament that involve the devolved administrations.”
He added: “Our parliament has been ignored, our government has been ignored… against the expressed wishes of the people of Scotland that voted in the (2016 EU) referendum and reaffirmed the right of the people of Scotland to determine their own destiny.”