A bill authorizing May to start EU exit talks has passed its final vote in Parliament's upper chamber, the House of Lords.
The House of Commons had approved the bill weeks ago, but the Lords fought to amend the legislation, inserting a promise that EU citizens living in the U.K. will be allowed to remain.
They also added a demand that Parliament get a "meaningful" vote on Britain's final Brexit deal.
Both amendments were rejected Monday by the Commons, and the unelected Lords then backed down and approved the bill.
May is now free to invoke Article 50 of the EU's key treaty, triggering two years of exit negotiations, by her self-imposed deadline of March 31.