Bjorn Kjos, founder of leading European low-cost transatlantic airline Norwegian Air, predicts Brexit will leave fewer Britons able to afford to fly.
He said the dramatic slump in the pound since the referendum would inevitably ‘weaken’ passenger traffic.
‘Most of the passengers flying to Spain from Birmingham and Manchester are pensioners and their income will not go up,’ he said. ‘And the pound is going down and that will make it more expensive for them to travel.’
Kjos also suggested that some EU companies could be forced to quit Britain altogether.
O’Leary has previously said Ryanair might stop internal UK flights from the end of next year.
Kjos, whose airline flies from British airports to the Continent and the US, said EU operators offering internal UK flights could fall victim to a tit-for-tat row over flying rights.
Speaking on board a Norwegian Air flight from Seattle to Oslo with its first long-range Boeing 737 Max 8 aircraft, Kjos said he thought the UK would probably be happy for EU-based airlines to fly within the UK. But he believes EU airlines might object to UK airlines operating flights within Continental countries.
‘I think the UK would say “yes” to EU airlines within the UK domestic market because they are very open-minded,’ he said. ‘But some EU member states would try to block it so then why should the UK allow it on their side? That is not fair and they would have to retaliate.
‘In the worst case it would revert to country by country agreements, but that would favour the UK because they have bilateral agreements with virtually every state in the world.’
Norwegian Air – which flies from Gatwick, Edinburgh and other UK cities – currently operates 56 routes across Europe and in North and South America.
It offers flights across the Atlantic from the UK for as little as $99 (£76) each way. The budget price harks back to the era of Laker Airways, which pioneered cheap flights to and from the US in the 1970s and early 1980s.
Norwegian Air has adorned the tailfin of its latest aircraft, left, with a picture of Laker Airways founder Sir Freddie Laker, who died in 2006.