Brexit secretary David Davis has confirmed a bill on triggering Article 50 has been introduced to the House of Commons.
It comes after the Prime Minister suffered defeat in a historic legal battle at the Supreme Court earlier this week - ruling Parliament must vote when to trigger the Article.
The Government was thereby forced to draw up the legislation - which it is thought will be rushed through the commons within two weeks.
ITV News Political Correspondent Carl Dinnen tweeted a copy of the bill, writing: "132 words to take us out of the EU".
Speaking after the Bill's introduction, Brexit Secretary David Davis said: "The British people have made the decision to leave the EU and this Government is determined to get on with the job of delivering it.
"So today we have introduced a Bill in Parliament which will allow us to formally trigger Article 50 by the end of March.
"I trust that Parliament, which backed the referendum by six to one, will respect the decision taken by the British people and pass the legislation quickly."
- What does the Bill say?
- What happens now?
The Bill will now be rushed through Parliament in order to meet Theresa May's deadline for triggering Article 50 by the end of March.
A second reading - the first Commons hurdle for the Bill - will take place on Tuesday and Wednesday. Some MPs are expected to oppose it outright.
It will then undergo its committee stage the following week, where the Government will face numerous attempts to amend the legislation from MPs on all sides.
The Liberal Democrats, for example, have vowed to oppose the Bill unless there is a guarantee of a fresh public vote on the final Brexit deal agreed with Brussels, while the SNP has indicated its MPs will table 50 amendments to the legislation.
After clearing the Commons, the legislation will be passed to the House of Lords - where the Government does not have a majority - for further scrutiny.