Brexit turmoil for Tory leadership contenders as negotiations shut down and no-deal vote on the horizon

Candidates to replace Theresa May as prime minister have suggested they could secure a new deal by the Halloween deadline

Contenders to replace Theresa May as prime minister have been dealt a double blow to their hopes of persuading voters that they can deliver a better Brexit.

European Commission president Jean-Claude Juncker flatly rejected any renegotiation of the withdrawal agreement struck with Ms May last November.

And House of Commons speaker John Bercow set up a constitutional clash with potential future prime ministers like Boris Johnson by insisting that MPs will have an opportunity to block a no-deal Brexit.

Leadership front-runners including Mr Johnson and Dominic Raab have made clear that they want to renegotiate Ms May’s deal, but are ready to leave without agreement on the Brexit deadline of 31 October if necessary.

Mr Johnson has vowed that the UK will leave on Halloween “deal or no deal”. And Mr Raab has said that there is still time to change the controversial backstop arrangements for the Irish border and negotiate a legally binding route for the UK to leave unilaterally.

Meanwhile, foreign secretary Jeremy Hunt said he was ready to form a new negotiation team taking in figures like the DUP’s Arlene Foster and European Research Group chair Jacob Rees-Mogg to persuade Brussels that an amended deal could get through parliament.

But an exasperated Mr Juncker gave short shrift to such plans, telling reporters at a Brussels summit: “I was crystal clear. There will be no renegotiation.”

The agreement between the EU and Ms May to delay Brexit until Halloween included a commitment not to seek a renegotiation of the deal. And there is no appetite for further talks from a team of EU officials whose term in office comes to an end in November, when chief negotiator Michel Barnier is slated as a potential replacement for Mr Juncker as commission president.

Meanwhile, Mr Bercow said that any suggestion a no-deal Brexit could be engineered by simply running down the clock to the end of October was “for the birds”.

Liberal Democrats have warned that a no-deal Brexiteer in Downing Street could even suspend Commons sittings for the vital period this autumn to prevent MPs from finding a way to stop the UK crashing out.

And the Institute for Government has warned that, with the death of Ms May’s Withdrawal Agreement Bill – which Downing Street has now accepted will not be tabled in parliament – MPs may have no procedural path to stand in the way of no deal.

But the speaker told a US think tank: “The idea that parliament is going to be evacuated from the centre stage of debate on Brexit is unimaginable.”

He agreed leaving without a deal was the default position, but added: “There is a difference between a legal default position and what the interplay of different political forces in parliament will facilitate.”

As the crowded field of would-be leaders swelled to 10 with the announcement by housing minister Kit Malthouse that he will run, Ms May warned her eventual successor not to leave the EU without a deal.

Arriving at the Brussels summit, the prime minister said she was “not going to comment on the views of individual candidates”, but added: “I continue to have the view that it’s best for the UK to leave with a deal.”

Mr Bercow, who is suspected by Brexiteers of favouring a Final Say referendum, risked stepping into the leadership contest by praising both Mr Hunt and environment secretary Michael Gove as “extremely capable ministers” with “intellectual self-confidence (and) communication skill”, as well as hailing their “pursuit of consensus”.

Mr Hunt warned that the Conservatives were facing “destruction” as a party if a new leader forces a general election before delivering Brexit.

His comment was widely seen as a warning against the election of a no-deal Brexiteer, who could be immediately ousted in a no-confidence vote backed by Remain-supporting Tories, triggering a general election.

Mr Hunt told BBC Radio 4’s Today programme: “We must not go back to the electorate asking for their mandate until we’ve delivered what we promised we would do last time, which is to deliver Brexit. It would be absolutely catastrophic for us as a party.”

But rival candidate Esther McVey, who favours no deal, retorted: “Political suicide actually lies in not having a clean break from the EU and not leaving on 31 October.”

The BBC announced it will host a live TV hustings in the middle of June, inviting all contenders still in the race to take part. Mr Raab and health secretary Matt Hancock have already challenged their rivals to a televised debate, amid speculation that Mr Johnson may shy away from the showdown.

Mr Hancock said: “I’m delighted that broadcasters have agreed to hold TV debates – this is a contest that affects the whole country, so we should engage the whole country in this process.”

The chair of the National Conservative Convention, Andrew Sharpe, has invited all candidates to a hustings on 15 June, when the group had been planning an emergency meeting to hold a vote of no-confidence in Ms May.