Willie Walsh has warned that as many as four European airlines could ultimately go bust this winter should economic conditions worsen.

The IAG chief executive told the conference that even after the failure of Monarch and Air Berlin, and beleaguered Alitalia’s ongoing struggles, the continent’s airlines remain largely safe.

However, he said a failure by many airlines to reform business practices could yet cost them, and that cracks could already be appearing in the market.

Oil remained a threat particularly after its recent price increase, he said, while the strong dollar meant that airlines largely dealing in euros and pounds remained vulnerable.

He added: “There are other airlines that are weak and may face challenges. There is a handful – I’m thinking of three, maybe four – airlines that will face a challenge this winter, and it won’t take much to see them in great difficulty.”

“Already we have seen a number of airlines fail this year – they were airlines that were fundamentally weak and the economic environment didn’t help them. In our industry, once someone is thought to be weak, the industry will target them.

“We have had a fundamental restructuring and none of our competitors did. Alitalia never restructured. Once the flow of foreign money from Etihad was turned off, it went bankrupt. It was always going to go bankrupt as they refused to change. They have failed to realise the industry has changed.”

He remained positive about the apparent impasse in Brexit talks, saying IAG planned to continue operations as normal as he believed a deal would be struck.