Boris Johnson's pledge to remove the controversial backstop from the Withdrawal Agreement is not enough for the European Research Group to back his proposed Brexit deal, ERG deputy chairman Mark Francois has told ITV News.
The de facto whip of the ERG confirmed he would push the Eurosceptic wing of the Conservative Party to vote against the party's new leader, a block vote which will increase the prospect of Britain leaving the EU without a deal.
Mr Johnson’s revised plan - which is currently being negotiated with EU leaders - would remove the Northern Ireland backstop but leave the rest of the Brexit deal unchanged.
Asked by Brand in his Westminster office if it was enough to win ERG support, Mr Francois said: "No. Prior to the first Parliamentary ballot - when Boris was all desperate for the ERG to vote for him - he had a meeting in the room next door to here with the senior leadership of the ERG and he absolutely, adamantly promised us that the Withdrawal Agreement was dead.
"He said it several times. Now, if a politician makes an absolute commitment, to me, I expect them to keep their word whether they’re a prime minister or a parish councillor.
"So ... I’m not voting for the Withdrawal Agreement and I suspect neither will many of my colleagues."
Tory eurosceptics are demanding other negotiated elements are amended, including the transition period length and the £39 billion divorce bill.
Mr Francois, a prominent critic of Mrs May, also predicted a backstop-less Brexit deal would still be met by a majority of opposition if it was put to MPs.
"It’s the House of Commons that voted down the Withdrawal Agreement, it wasn’t just the ERG and it was voted down decisively three times and if the prime minster were to bring back pretty much the same withdrawal agreement, I expect he’d get pretty much the same result," he said.
"So I don’t think it’s going to go through."
However, Mr Francois told ITV News he supported the government's plan, announced on Wednesday, to prorogue (effectively suspend) Parliament and deliver a new Queen's Speech on 14 October.
"That’s normal, you would normally prorogue Parliament before a Queen’s Speech. That is not some constitutional outrage, it’s what usually happens," he said.
"And we’ve had the longest session of Parliament for many, many years so we’re due a Queen’s Speech."
Pressed by Brand on whether the timing of the announcement was tactical ahead of the 31 October departure date, he said: "If the Queen’s speech is on October 14, you’ve still then got three weeks until Brexit day so its not as if the House of Commons wouldn’t have an opportunity to debate these matters."
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