A spokesman for Downing Street has said Parliament will be given "a say" on the process of the UK's departure from the European Union.
But the spokesman declined several opportunities to say whether MPs will be given a vote in the Commons on triggering Article 50, when pressed on the issue by reporters.
His comments left open the possibility that Mrs May will launch the negotiations without seeking MPs' approval, and will later give them an opportunity to express their views in a debate without a vote.
The spokesman also confirmed that Mrs May will not hold a second Brexit referendum on the outcome of the Article 50 negotiations and will not call an early general election to seek voters' approval of the eventual deal, as Labour leadership candidate Owen Smith has demanded.
The Number 10 spokesman told reporters: "There is no legal obligation to consult Parliament before triggering Article 50 - that position has been well set out since the decision to leave the EU was taken by the British people.
"We have been very clear, Parliament will have its say. Triggering Article 50 won't happen before the end of the year. At the moment, the work is full speed ahead on establishing a UK-wide approach to Brexit and setting out a clear set of objectives for negotiations going forward.
"Parliament will have a say on Article 50 and the relationship of Britain going forward as it exits the EU or starts the process of exiting the EU... When Parliament will have a say will be something that will be resolved over the coming months.
"Parliament will be involved, it will have a say, opinions will be aired, but I would just say that the referendum bill was passed by a majority of six to one in the Commons and that the PM has been clear that the will of the people who voted to leave the EU must be respected."