Airline chiefs expressed sharply differing views on the impact of Brexit, with Ryanair chief O’Leary forecasting “a crisis” in April 2019, but IAG boss Willie Walsh insisting all would be “resolved”.

Speaking at an Airlines for Europe (A4E) summit in Brussels, O’Leary dismissed Walsh’s view, saying: “Willie has to play the game.”

He insisted: “There will be a real crisis in April 2019. There will be a disruption of flights. It is in the interests of the French and Germans to push on this issue.”

Lufthansa group chief executive Carsten Spohr agreed with O’Leary, saying: “It is in the interests of the EU to put pressure on the UK. Our industry is more a tool [in the Brexit process] than an issue itself.”

Spohr argued: “We as an industry could solve this. But this is a hard negotiation and they all have sharp weapons in their pockets.”

He added: “Brexit is terrible. None of us want this.”

However, Walsh insisted Brexit would not be an issue, while adding: “There is no better industry at dealing with disruption than us.”

He said: “I’m a firm believer that this all gets resolved. It is not in the interests of Air France-KLM [to lobby for a breakdown]. KLM has 52 flights a day between the UK and Amsterdam.”

Walsh also dismissed a Financial Times (FT) report on March 6 which suggested UK airlines’ Atlantic routes are at risk because “the US is offering Britain a worse Open Skies deal after Brexit than it has as an EU member”.

The IAG boss said: “The FT says there will be no agreement with the US. It is complete and utter nonsense. The Financial Times is wrong. I would not believe anything I read in the FT.”

He pointed out the article reported: “A senior government official said it was ‘nonsense to suggest planes won’t fly between the UK and US post-Brexit’ [and] the state department said it wanted ‘the smoothest possible transition’.”

Walsh said: “I’m completely relaxed. The UK government is determined to reach agreement with the US and the US agrees.”

New easyJet chief executive Johan Lundgren also agreed, suggesting: “It’s inconceivable that any politicians would want flights grounded.”

But O’Leary insisted: “I disagree.” He even suggested: “It is in our interests that aircraft are grounded – not for long. People need to realise things are going to change. They are going to lose cheap holidays. They were lied to.”

Spohr said: “I agree with Michael.”

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