An aviation deal tops the list of travel industry demands as Britain begins the Brexit process.

That is the view of Abta chief executive Mark Tanzer, who described an agreement on UK-EU air access as paramount.

Prime Minister Theresa May triggered the Brexit process yesterday in a letter delivered to European Council president Donald Tusk, and the government will publish a Great Repeal Bill today.

Tanzer highlighted the sector’s concerns, saying: “The most pressing aspect is an aviation deal because there is no World Trade Organisation fall-back position and the industry needs to be able to plan on the basis of understanding what access [to the EU] there will be.”

The Abta chief said he believes ministers understand the importance of clarifying the situation on air travel, but he fears a political hold-up.

He said: “We want certainty, and I believe the government has taken it on board. [But] I’m worried about the inability to predict the politics of this.

“It’s not just a straightforward trade negotiation. Politics could cut across it dramatically.

“Economic logic would say ‘Let’s carry on’ [as we are] because it benefits both sides to have open trade, but no one knows if we will.

“The issues have been put on the table, but the government has hundreds of priorities. The task is gargantuan and everybody is saying their issue is the most important.”

Tanzer added: “The government has adopted a no-comment strategy [so far], but I think that will begin to change [after] this week. Insisting ‘We’re not saying anything’ will become more and more difficult.”

Abta’s Travel Convention in The Azores in October will provide an opportunity to reflect on the first six months of Brexit negotiations.

Tanzer said: “Either we’ll see the shape [of Brexit] by then or, more worryingly, we won’t.”

The association will also present an opportunity to discuss the policy issues arising out of Brexit at its annual Travel Matters conference in June.

Travel Matters will be held on June 28 at RSA House in central London.

World Travel and Tourism Council president and chief executive David Scowsill called last week for May to focus on four “key issues” facing travel.

He highlighted the need for labour mobility, visa-free travel and investment in border processes as well as the need to maintain a single aviation market in Europe.

Scowsill told Travel Weekly: “These issues are critical. [But] my guess is none of them will get clarity for two years.”