Airline body IATA is optimistic that the relevant governments will take the necessary steps to ensure continuity of air services after the UK's scheduled departure from the European Union on 29 March 2019.
While flagging his concerns about continued uncertainty, IATA director general Alexandre de Juniac says he does not expect air services to be disrupted in the planned transition period.
"We see the negotiators from both sides aware of what is at stake and aware and conscious of the need of doing everything to prevent a drop in the traffic," said de Juniac during IATA's global media day in Geneva on 12 December. "So they will do what they both can to maintain the connectivity."
IATA chief economist Brian Pearce adds: "One of the key issues for [London] Heathrow is connections to the US, and the UK has concluded an open-skies agreement with the US. But there is a lot of uncertainty still, which is bad for the industry."
Though encouraged by the discussions aimed at ensuring continuity of flights after Brexit, de Junaic notes: "We don't have any special insight on how this will play out. But we do know the industry needs more clarity than we currently have.
"Time-sensitive critical supplies arrive in the UK by air. So understanding customs formalities is vital," he says. "And as airlines are already selling tickets for the post-Brexit period, speed in finalising arrangements is essential."
De Juniac was asked about Brexit as UK prime minister Theresa May prepared to face a confidence vote. She emerged victorious, but it has done little to resolve the political uncertainty around the UK's exit from Europe, and there is a range of outcomes that remain possible.
"Brexit is not good news for this industry, and we have always said it," says de Juniac. "So whatever could limit the Brexit consequences is good news for aviation."
Pearce adds: "We think there will clearly be some damage to the UK economy if Brexit happens. In terms of the industry itself, there has already been cost imposed on airlines adjusting their ownership structure and getting [additional] operating certificates."