The Commons endorsed the legislation by votes to after the government saw off a desperate bid by more than 100 Remoaners to wreck it. In the first of a crucial set of votes in the Commons, a 'wrecking' amendment that would have effectively killed the law was defeated by 336 to 100. The House then gave the Bill its second reading by another huge margin, despite the opposition from Labour MPs, the SNP and most Liberal Democrats.
Minutes before the vote, two Labour MPs dramatically quit the frontbench to defy Jeremy Corbyn and vote against the key legislation.
Some 33 of the party's MPs backed the wrecking amendment tabled by the SNP. More are thought to have voted against the Bill's second reading.
A handful, such as Chris Bryant and Mary Creagh, opposed the legislation despite their constituents having decisively backed Brexit in the referendum.
Dozens more voted in favour of holding the EU referendum two years ago - but voted against implementing the result.
Just one Tory MP, arch-Europhile Ken Clarke, appears to have joined the Brexit opponents in the division lobbies.
The votes came after two days of bad-tempered and impassioned debate in parliament.
Mrs May earlier confirmed she will publish a white paper on her Brexit plans tomorrow.
Ex Chancellor George Osborne - who led the charge for Remain - earlier warned opposing Brexit risked a 'constitutional crisis'.
Meanwhile, Jeremy Corbyn's EU nightmare gathered pace as two more members of his top team quit to vote against Brexit.
Dawn Butler and Rachael Maskell resigned rather than fall into line with the leadership's stance of supporting legislation that will trigger Article 50.
More could follow them out of the door after the key votes.
Mr Corbyn tried to put a brave face on the chaos, thanking the pair for their work and saying they were still 'assets to the party'.
The government secured a thumping majority in both the key Commons votes tonight