The bill empowering the government to begin the formal process of leaving the European Union is due to reach its final stages in the Commons later.
MPs will debate further amendments to the Brexit bill – allowing Article 50 to be triggered – for up to seven hours before a final vote due at 20:00 GMT.
The vote could cause more Labour rifts – with its MPs told to back the bill.
On Tuesday night, the government saw off attempts to add conditions to the bill as a Tory rebellion was avoided.
The vote means the government has now cleared two days of debate in the Commons without the bill being amended.
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The Commons will debate the final set of amendments later, including on key principles for the negotiation process, before the bill goes to its third and final reading in the Commons.
The final debate will then end with a vote by MPs, which could expose further rifts within Labour.
Jeremy Corbyn has ordered his MPs to support the government’s bill, whether his party’s amendments are accepted or not, has believes it would be undemocratic to ignore the will of the people, as expressed in last June’s EU referendum.
However, shadow business secretary Clive Lewis has vowed to oppose the bill unless Labour amendments are passed in the Commons.
Once the bill passes the Commons, it will be debated in the House of Lords after it returns from recess on 20 February.
On Tuesday, MPs rejected a bid by Labour’s Chris Leslie to force the government to consult Parliament on the deal struck with the EU before it is finalised.
It came after ministers pledged that a “meaningful” vote would be offered.
Labour and some Tories had pushed for MPs to have a decisive say on the final terms, but the 326 to 293 vote meant the bill remained unchanged.
Seven Conservatives rebelled, while six Labour MPs voted with the government.
Several other attempts to amend the legislation – which if passed will authorise the prime minister to formally begin Brexit negotiations under Article 50 of the Lisbon Treaty – were also rejected during more than seven hours of debate.
‘A meaningful vote’
Theresa May has already promised Parliament will get a say on the final deal, but critics, including some Conservatives, said they wanted more than the “take it or leave it” vote being offered.
Any possibility of a major Conservative rebellion appeared to be halted by comments from Brexit Minister David Jones.
Mr Jones said MPs would get a say on the final draft Brexit agreement before it was voted upon by the European Parliament.
“This will be a meaningful vote,” he told MPs.
“It will be the choice of leaving the EU with a negotiated deal or not.”
Downing Street played down claims the government’s position had changed.
But Labour’s font bench claimed the move as a “significant victory” in response to its repeated demands for a “meaningful” vote at the end of the two-year negotiation process.