Political uncertainty on Brexit in Britain will lead to a fresh “crisis” late this month, a leading political commentator warned UK corporate travel leaders.

BBC broadcaster Steve Richards told the Guild of Travel Management Companies’ (GTMC) conference in Ireland: “MPs can’t agree on what should be proposed to the EU summit in June.

“Theresa May will probably present two options, EU leaders will reject both and it will be another moment of crisis.”

Richards told the GTMC: “It’s difficult to predict what will happen in the next hour let alone the next few months. [But] Europe has brought down three UK prime ministers – Thatcher, Major and Cameron – and May will be another.”

He said: “The June [EU] summit will not be decisive. We’ll move to October, [when] there has to be an agreement because the Brexit ratification process will take at least three to four months.

“May wants to be able to say to Parliament [in October], ‘Accept the deal or it’s no deal’. If she loses, the prime minister would have to go.”

He added: “The clock is ticking yet nothing is in place. Will there be a sector-by-sector agreement on [EU] labour? Will there be a clear idea of the [Brexit] arrangements by October? I don’t believe there can be.

“May is going to have to ask for more time. The government will say ‘We’ll sort out the detail in the transition period’.”

Richards suggested businesses should prepare for Britain to remain in the customs union but accept the UK will be outside the single market.

He told the GTMC: “There is a majority [among MPs] in the Commons for Britain to be part of the customs union, so one way or another it seems Britain will be in a customs union.

“[But] it looks as if Britain will leave the single market and struggle to get anywhere near it.”