THERESA May has rejected claims that UK Cabinet divisions are making Brexit negotiations with the EU harder as the Prime Minister insisted she was a “woman of her word,” saying she had not reneged on a deal with Tory Remainers over the Brexit Bill.

When asked what message she had for Foreign Secretary Boris Johnson after he was recorded expressing concern the UK could end up remaining in orbit around the EU and not fully free to make trade deals, Mrs May said: "The message is Government has agreed that we will have an independent trade policy. We will be free to negotiate those trade deals around the rest of the world."

She explained how in the week beginning July 9 the UK Government would publish a White Paper on Brexit, setting out in more detail its ambition for a future relationship with the EU.

The PM told BBC1's The Andrew Marr Show that she could not agree to any EU move that would harm the Union of the United Kingdom by creating a trade border between Britain and Northern Ireland, declaring: "That's not right. That's not acceptable."

Ahead of a debate in the House of Lords tomorrow on the EU Withdrawal Bill and a crunch, potentially knife-edge vote on Wednesday when the amended legislation returns to the Commons, Mrs May insisted she was a woman of her word after some Tory rebels expressed fears they were not getting the compromise deal they believed had been on offer over Parliament having a greater influence on Brexit.

"I did indeed meet a group of my fellow MPs. I listened to their concerns and I undertook to consider their concerns. And the next day I stood up in Prime Minister's Questions and said I'd put an amendment down in the House of Lords. I've done exactly that.”

Facing claims of betrayal by some pro-EU colleagues, Mrs May insisted that she and her Cabinet colleagues recognised the concerns some people had about the role of Parliament in the Brexit process but she made clear she would not budge on the primacy of Government in the talks with Brussels, saying: "Parliament cannot tie the hands of Government in negotiations."

However, her Tory colleagues Dominic Grieve made it clear the Conservative rebels did not intend to back down on getting Parliament more say on Brexit.

Asked if they did not secure a so-called “meaningful vote” on the final Brexit deal, they would oppose the Government in Wednesday’s vote, the former Attorney General replied: “The meaningful vote pledge has to be fulfilled, yes.”

Asked if the rebels could collapse the Government by voting against it, he told BBC1's Sunday Politics: "We could collapse the Government. And I can assure you I wake up at 2am in a cold sweat thinking about the problems that we have put on our shoulders. The difficulty is that the Brexit process is inherently risky."

Robert Buckland, the Solicitor General, insisted UK ministers intended to press on with their own meaningful vote amendment, which suggested a Government motion on the final deal could not be amended; rebels believe this means the meaningful vote would, therefore, not be meaningful.

Mr Buckland stressed that while Tory rebels argued the vote they wanted would only be advisory, he stressed that even this vote could have a political consequence and send a signal to Brussels that the UK Government was not in control of its own negotiating strategy. “There is a political contest to all of this,” he insisted.

Ahead of the Lords debate tomorrow, Lord Newby, who leads the Liberal Democrats in the upper chamber, accused Mrs May’s plans on the Brexit bill as “breathtaking in their arrogance and deceit”.

“Having reneged on a promise made to her own colleagues, it is clear she cannot be trusted. The Government’s current proposal would neuter Parliament if the Government failed to reach a Brexit deal. This is simply unacceptable,” he declared.

Lord Newby went on: "Parliament must be given a meaningful vote on all possible outcomes of Brexit and this must be guaranteed in writing in the Withdrawal Bill.

“The Conservatives are making a complete mess of Brexit. They are gambling with the country’s future purely in an attempt to patch over divisions in the Tory Party.”

He added: "At some point there will be a reckoning: either with a cobbled-together Brexit deal or if the negotiations fail. At that point, Parliament must be able to decide amongst all the options, including giving the people a final say on our future relationship with Europe.”