The historic post-Brexit trade deal reached between Prime Minister Boris Johnson's government and the European Union was signed into U.K. law by Queen Elizabeth II on Thursday morning.

Why it matters: The law will come into effect at 11pm Thursday U.K. time when the Brexit transition period officially ends.

• The House of Commons voted 521 to 73 on Wednesday in favor of the bill, which was approved by the U.K. House of Lords later that night — marking the last major hurdle needed to implement the deal.

The state of play: Johnson's government was criticized for giving Parliament just days to scrutinize one of the most significant pieces of legislation in decades, but even members of the opposition Labour Party ended up voting for the agreement in order to stave off a potentially catastrophic "no-deal" Brexit.

• The deal, which fundamentally reshapes the U.K.'s relationship with its closest and largest trading partner, will now go to receive royal assent and becoming law.
• European heads of state came out in support of the deal earlier this week, while the European Parliament plans to scrutinize the agreement and officially vote on it after Jan. 1 — though it will be applied on a provisional basis in the meantime.

Go deeper: U.K. and EU reach historic post-Brexit trade deal

Editor's note: This story has been updated with details of the House of Lords vote and the signing of the bill into law.