ENVIRONMENT Secretary Michael Gove has cancelled a planned trip to laboratories near York this afternoon as the Brexit crisis deepens.

Mr Gove had been due to come to the National Agri-food Innovation Campus at Sand Hutton for the official launch of pioneering testing equipment for pesticides and other chemicals in running water.

But he decided to stay in London in the wake of Prime Minister Theresa May’s Brexit announcement yesterday.

His decision came after Brexit Secretary Dominic Raab, Northern Ireland minister Shailesh Vara and Work and Pensions Secretary Esther McVey resigned this morning,  in a massive blow to the PM’s plans.

Organisers said the event at Sand Hutton would still go ahead in a low-key way in his absence.

Mrs May has been presenting her deal on Britain’s EU withdrawal to the Commons, while leading Tory Brexiteer Jacob Rees-Mogg has directly raised the spectre of a leadership challenge to her.

Mr Rees-Mogg, chairman of the European Research Group, highlighted areas of the deal where he said the “honourable” Prime Minister had reneged on promises over leaving the customs union, maintaining the internal integrity of the UK and leaving the jurisdiction of the European Court of Justice.

He told MPs: “As what my right honourable friend says and what my right honourable friend does no longer match, should I not write to my right honourable friend the member for Altrincham and Sale West?”

This was a reference to Sir Graham Brady MP, the chairman of the Tory 1922 committee, to whom MPs must write to express no confidence in a leader in order to trigger a challenge.

Mrs May replied that “some difficult choices have had to be made” to avoid a hard border on Ireland, adding: “It is not only our intention, but we will be working to ensure that protocol does not have to be put into place.

Conservative MP Andrew Bridgen (North West Leicestershire) suggested Mrs May should step down following her own transition period.

He told the PM: “The Prime Minister is well known for her dancing – sadly having seen the withdrawal agreement it’s now clear whose tune she’s been dancing to.

“(Mrs May) campaigned for Remain, she voted Remain, now surely it’s in the national interest for her to leave – perhaps following a short transition period.”

Mrs May replied: “Can I note the way in which he carefully tried to weave into his question various references to matters that are not perhaps entirely relevant to the withdrawal agreement and the political declaration.”

The PM said every MP will have a decision to take when the deal is before them.

Explaining his resignation, Dominic Raab said he believed Theresa May should stay on as Prime Minister but change course over Brexit.

“I have been fighting for a good Brexit deal but the terms proposed to the Cabinet yesterday had two major and fatal flaws,” he told the BBC.

“The first is that the terms being offered by the EU threaten the integrity of the UK.

“The second is that they would lead to an indefinite, if not permanent, situation where we are locked into a regime with no say over the rules and the laws being applied, with no exit mechanism.

“I think that will be damaging for the economy but devastating for public trust in our democracy.”

He said he still respected the Prime Minister and held her in “high esteem” adding: “I think she should continue but I do think we need to change course on Brexit.”