Luke Petherbridge, head of public affairs at Abta, said the industry needed to make sure planning for a hard Brexit “remains to the fore” in the current political environment.

“No-deal is not dormant, it’s having a nap – it will come back in October,” warned Petherbridge, during a session on Brexit at Abta’s annual Travel Law Seminar in London.

Petherbridge added it was unlikely the UK would leave the EU without a deal before the current Brexit date of 31 October, with another extension being the most likely outcome.

But he said there could still be a situation where a no-deal Brexit happens in the autumn, especially with a new Conservative leader to be elected later this summer after prime minister Theresa May announced on Friday (24 May) she would step down on 7 June.

Neil Baylis, partner at law firm Mishcon de Reya, said UK airlines would still be able to fly to EU countries if there was a no-deal Brexit until 29 March 2020, as long the British government allowed EU airlines to fly to the UK.

Baylis added there could be delays at the border for passengers using Eurostar and Eurotunnel train services from the UK to the continent.

“There has been a pragmatic approach on both sides with no suggestion that people are going to stop trains running,” he said. “But there are likely to be delays if border controls are properly enforced, which could block up the system.”

Baylis said there could also be issues for “posted” workers with travel companies having to “get into the weeds” of the local laws in member states.

“If you’re commiting to sending a guide, are you still able to do that?” he said.

Narinder Sanotra, legal director UK & Ireland, for travel management company CWT, said: “We have been doing contingency planning for a no-deal Brexit. One of the biggest issues is the potential impact on staff, which can be quite unnerving. The key is communication – the more information [they have], the more settled they feel.”