Ryanair CEO Michael O’Leary has warned Boeing job cuts could result at the airline if further MAX delays occur.

O’Leary has warned that some of Ryanair’s 17,500 staff could be made redundant if the Boeing 737 MAX stays grounded for any longer than expected.

His comments come after Ryanair’s first-quarter results revealed a 24 per cent slump in profits. The low-cost carrier has said arresting the impact of a longer than expected return-to-service for the 737 MAX is a key component to its financial strategy going forward.

Boeing is currently working on a software update to the 737 MAX that will provide “additional layers of protection if the AOA [Angle of Attack] sensors provide erroneous data”, which awaits approval by the United States Federal Aviation Administration (FAA).

Boeing chairman, president and CEO Dennis Muilenburg told investors on a conference call last week that he remains confident the grounded 737 MAX will return to service by October this year, but warned the manufacturer may have to halt production on it.

Ryanair isn’t expecting to fly the MAX until early next year.

“We were originally expecting 58 aircraft for the summer of 2020 – that’s now 30 at best. It may well move to 20, it could move to 10, and it could well move to 0 if Boeing don’t get their s**t together pretty quickly with the regulators,” O’Leary said on an earnings call following the release of Ryanair’s first-quarter results.

The FAA has consistently urged it is not operating on a strict timeline for approval, but said yesterday that it hopes global regulators will simultaneously approve the 737 MAX return-to-service when the time comes.

Acting FAA Administrator Dan Elwell told members of the United States Congress that the agency “hopes to achieve near simultaneous approval from the major civil aviation authorities around the world”, according to a Reuters report.

He added that every regulator will make its own determination, but said the FAA is “working with our colleagues from the European Union, Canada and Brazil” to address concerns.

As a result of the continued grounding of the 737 MAX, United Airlines has been forced to suspend one of its routes.

The suspension, which will take effect 3 September, will temporarily put a stop to services between Chicago O’Hare and Leon, Mexico (BJX).

“We have made the decision to temporarily suspend service between Chicago O’Hare and Leon, Mexico … in order to help mitigate issues resulting from the grounding of the MAX aircraft and better optimise our resources to address customer needs in markets served from Chicago,” a United Airlines spokesperson told Travel Weekly.

Customers travelling to Leon will continue to be served through United’s Houston hub, which operates four daily services between Houston to Leon year round.

United has 14 Boeing 737 Max 9s in its fleet – a slightly larger model jet than the MAX 8 – which have remained grounded since March.

United is the second North American airline to announce it will temporarily suspend a service as a result of the grounding.

American Airlines, which has 24 MAX 8 aircraft in its fleet, cancelled direct flights from Dallas to Oakland earlier this month. The route will remain cancelled through at least 3 September.

American has cancelled flights for the 737 MAX through to 2 November, with the latest extension the fourth time that the airline has extended cancellations on the jet.

This followed a separate announcement by Southwest Airlines that it would cease operations at Newark Liberty International Airport (EWR) effective Sunday, 3 November as a result of the grounding of the 737 MAX.

It’s never our desire to leave any community that we serve, but Southwest has made the difficult decision to discontinue service at Newark Liberty International Airport (EWR),” a Southwest spokesperson told Travel Weekly.

“This was not an easy decision to make, but we must optimize our aircraft and resources to meet customer demand in other markets.”

All Southwest employees at EWR are being offered positions at New York’s LaGuardia Airport, or being allowed to bid for other positions in the Southwest network.

Southwest reportedly has the most 737 MAX jets in its fleet out of any US-based airline with 34.