The European Union (Notification of Withdrawal) Bill will receive Royal Assent in the coming days, meaning that the government is on course to formally trigger Article 50 of the Treaty on European Union before the end of this month as planned.
In a statement to the House of Commons, Theresa May described the passage of the bill as "a defining moment for our whole country as we begin to forge a new relationship with Europe and a new role for ourselves in the world".
"The 137-word bill which is about to become law is historic," said parliamentary agency and government affairs expert Richard Bull of Pinsent Masons, the law firm behind Out-Law.com. "In authorising the UK to give notification of its intention to withdraw from the EU, it allows a process to begin which will permanently change the UK’s relations with other EU member states."
"Parliament's next task will be to examine the Great Repeal Bill, scheduled for introduction in May. The supremacy of EU law, enshrined in our constitution since 1 January 1973, is about to become a thing of the past," he said.
The bill returned to the House of Commons on Monday evening, where MPs rejected two House of Lords amendments. Peers sought to guarantee the rights of EU citizens living in the UK; and to require that Parliament be given a vote on the terms of the final Brexit deal. By a majority of 139 peers agreed not to pursue the guarantee for EU citizens. They then backed down, with a majority of 156, on their amendment requiring both Houses to approve the EU deal..
Introducing the returned bill in the House of Lords, Lord Bridges of Headley told peers that the debate was "not the time, nor the place to return to the fray and insert terms and conditions to our negotiating position, still less to force the government to make a unilateral move on the status of EU nationals in the UK".
"The bill has only one purpose: to implement the outcome of the referendum result in June and respect the judgment of the Supreme Court, nothing more, nothing less," he said.
The minister asserted the view that the government should not be expected to guarantee the rights of EU citizens in the UK without a similar guarantee for the 900,000 UK citizens living in the EU.
The bill was introduced to Parliament in late January, after the Supreme Court ruled that the government needed the agreement of both Houses of Parliament before it could invoke Article 50. It is two clauses in length and concerned only with the exercise of the power to give notice to quit the EU, and not the ensuing negotiations. Once invoked, Article 50 triggers a formal two-year process of withdrawal from the trading bloc- subject to an extension which must be agreed by all Member States.
Hours before the debate, Scotland's first minister Nicola Sturgeon announced the Scottish Government's desire to proceed with a second referendum on Scotland's independence in the six months leading up to the UK's likely departure date from the EU, March 2019.
Sturgeon will ask the Scottish Parliament to approve the plans next week, on the grounds that leaving the EU counts as a 'material change in circumstances' justifying a second referendum. However, the UK government must give permission for any referendum to take place and it is likely that the timing, wording of the question and even the number of options on the ballot paper will be the subject of negotiations between both governments.