O’Leary, chief executive of the Irish airline, claimed yesterday that what he believed to be financial constraints on Norwegian may see the carrier struggle.

“Norwegian will go in four or five months. They are running out of cash… they are scrabbling around daily,” he said.

“Norwegian has huge aircraft orders that they don’t have the cash to pay for.”

A Norwegian spokesperson hit back at the claims – telling TTG O’Leary’s views "have no root in reality".

He added: "Norwegian has been profitable for the last 10 years, with a strong liquidity, together with owning a substantial share of Bank Norwegian which has a market value of over £1.6billion (NOK 17 billion)."

O’Leary maintained that he did not want to see Norwegian fail as he “likes that they are giving competition to BA” with its route strategy and product offering.  

Ryanair has been in talks with Norwegian for some time on offering connecting flights to its long-haul services – which O’Leary said were still taking place.

“We are still talking [to Norwegian], but I’m not sure they will still be flying in 12 months,” he added.

During a press conference in London O’Leary also questioned the future of Monarch Airlines, telling reporters: "Both Monarch and Norwegian are in trouble".

Considering the state of the aviation industry post-Brexit, O’Leary said he could foresee “four to five airlines emerging as main players over the next four to five years”, naming BA’s parent [IAG], Lufthansa, Air France-KLM, Ryanair and easyJet.

Although, he doubted that easyJet would remain independent in five years’ time, telling reporters there was a “50/50 chance” the carrier would merge and touted Air France as a possible future partner.

TTG contacted Monarch for comment.