A POSSIBLE future attempt by a Boris Johnson-led Government to "bypass" Parliament to pursue a no-deal Brexit "would be beyond a prime minister's powers", campaigner Gina Miller has said.

Miller said a letter from her legal team that went to Tory leadership contender  Johnson on Thursday "was to say that if he became prime minister that we believe that that would be beyond his powers, and also relying on the judgment in my case in 2017 where the Supreme Court expressly said that Parliament could not be bypassed".

Speaking about the prospect of prorogation of Parliament on Sky News's Sophy Ridge On Sunday, hosted by Niall Paterson, she said: "We think that it's beyond the Prime Minister's powers because Parliamentary sovereignty is actually the jewel in the constitutional crown and to bypass and to close the doors of parliament, we feel from the advice and the... case law we've looked at, that that would be beyond a prime minister's powers, it would be an abuse of his powers to close Parliament, to get through or to not get through, to limit the voice of the representatives that we all elect."

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Tory former international development secretary Priti Patel, who is backing Johnson said she was "not at all surprised" by possible legal action, as she hit out at the "absolutely relentless movement to delay Brexit".

She told Sky News: "It's now down to MPs and a new government to actually take action, not for third parties by going through the courts.

"I think that's exactly how it should have been previously as well, after 2016. After the referendum the Government was very clear back then that Brexit meant Brexit and that we were going to leave the EU.

"Instead we had a range of third-party anti-Brexit organisations and positions that chose to go to the court to derail basically the whole Brexit delivery and also to tie the hands of politicians, the Government and Parliament.

"That is simply not acceptable and quite frankly the British public are sick to death of this, they want to see a government now, with renewed conviction, get out there and do exactly what it said it will do, which is now to deliver Brexit.

"This should not be about the semantics of Parliament or just votes in Parliament or proroguing Parliament. We now have to get behind a new government."

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Work and Pensions Secretary Amber Rudd said she now accepts the option of a no-deal Brexit has to be part of the "leverage" in negotiations with the EU.

Rudd, who has previously voiced strong objections to leaving without a deal said she hoped there could be compromise on all sides - including from the pro-Brexit Tory European Research Group (ERG) on the issue.

"I have accepted that we now need to allow no-deal to be part of the leverage to make sure that people compromise more," she told BBC One's The Andrew Marr Show.

"I would hope that the EU will compromise and that the ERG will compromise too."

She said she was still concerned about the economic impact of no-deal, but added: "I am no longer saying that I will lie down in front of the bulldozers if it arrives."

Rudd, who is backing Jeremy Hunt for the Tory leadership, sidestepped a question about whether she had changed her position to ensure she could still sit in Cabinet if Boris Johnson won.

"I am not interested in talking about anybody's cabinet except Jeremy Hunt's," she said.

Amber Rudd said she would resist any move by the next prime minister to suspend Parliament in order to force through Brexit.

Boris Johnson has repeatedly refused to rule out proroguing Parliament if MPs try to block a no-deal break with the EU.

However the Work and Pensions Secretary told BBC One's The Andrew Marr Show: "I think that proroguing Parliament would be a mistake.

"MPs across both parties at every level think it is the wrong thing to do and I would urge any prime minister to put that aside."

She added: "I think I would use my own tactics to try to stop that happening and I encourage anyone else to consider their own version as well."