THERESA May has insisted Westminster cannot be allowed to "overturn the will of the British people" on Brexit.

The Prime Minister was speaking as she confirmed that the UK Government is expected to table a new amendment to her flagship EU Withdrawal Bill on Thursday, setting out in more detail the terms of the "meaningful vote" promised to MPs on the final Brexit deal.

On Tuesday, she saw off a threatened defeat on the issue in the Commons by assuring would-be rebels personally that she would take their concerns on board.

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But pro-EU Tories warned they remained ready to rebel if their demands were not satisfied by the compromise amendment.

The legislation is due to return to the Lords on Monday when it is expected peers will reverse the changes in the Commons to again demand MPs have the final say should the Brexit deal be rejected. This means that if Mrs May’s compromise amendment does not satisfy the potential Tory rebels, then they could vote against it when the issue goes back to the lower chamber in July.

Speaking at Prime Minister's Questions, Mrs May said: "We have seen concerns raised about the role of Parliament in relation to the Brexit process.

"What I agreed yesterday is that as the Bill goes back to the Lords we would have further discussions with colleagues over those concerns.

"I have agreed this morning with the Brexit Secretary that we will bring forward an amendment in the Lords."

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The PM said her approach would be guided by the principle that "the Government's hand in negotiations cannot be tied by Parliament, but we need to be accountable to Parliament".

She explained: "I cannot countenance Parliament being able to overturn the will of the British people: Parliament gave the decision to the British people, the British people voted to leave the European Union and as Prime Minister I'm determined to deliver that."

Mrs May was responding to a question from Conservative arch-Brexiteer Jacob Rees-Mogg, who said it was vital that any amendment preserved the separation between the roles of Government and Parliament.

Potential Tory rebels held back from a threatened revolt on Tuesday after a face-to-face meeting in which their party leader was said to have offer "personal assurances" on concessions.

Minutes later, all but two of the Tory MPs voted with the Government to reject a Lords amendment that would have given Parliament the power to tell the PM to go back and renegotiate the Brexit deal she secures from Brussels.

Moreover, senior pro-EU Tory Dominic Grieve withdrew his own amendment, which would have given MPs powers to dictate what the Government should do if no acceptable agreement were reached by February 2019.

He said Mrs May had promised to table a fresh amendment based on his own proposal for Parliament to be consulted on the way forward if no deal was agreed by the end of November.

The former Attorney General warned that if the Government failed to offer an adequate compromise, it would not be "the end of the matter". He argued that no government would survive if it tried to dispense with Parliament's input.

Remain-backing former minister Anna Soubry insisted that Mrs May had agreed at Tuesday's meeting to discuss all elements of Mr Grieve's amendment - including the measure to allow MPs to take control of the process if no Brexit deal is struck by February.

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"If the PM goes back on that, there will be no agreed amendment that I can support," she warned.

Former minister Stephen Hammond, who was present at Tuesday's meeting with Mrs May, said he "trusts entirely" the promises made by the PM. But he warned: "If those amendments don't come forward, I and a number of others will consider voting against the Government."