Even with the reduced flight schedule, it only expects half of its passengers to travel, the airline said.
It is currently flying around 1,700 passengers per day along much-reduced routes across Ireland and Europe.
Its current skeleton timetable is set to last until July, it said, and even between July and September, it only expects to run half of its previously-planned service of almost 500,000 passengers per day.
In a statement, it said: “When scheduled flights return in Europe, sometime in July, Ryanair believes it will take some time for passenger volumes to return.
“Consumer confidence will be impacted by public health restrictions, such as temperature checks at airports and face coverings for passengers and staff on board aircraft.”
The company said that it believes airline traffic will not return to pre-coronavirus levels for at least two years.
In response to the announcement, Brian Strutton, general secretary of the British Airline Pilots’ Association (Balpa), said: “Ryanair seems to have done a U-turn on its ability to weather the Covid storm. Aviation workers are now facing a tsunami of job losses.”
Mr Strutton called on the UK government to “stop daydreaming and keep its promise” to help the industry.
The news comes as British Airways announces up to 12,000 job cuts - equivalent to 29% of staff - and said that it may be forced to close its London Gatwick hub completely, as it consolidates all traffic to London Heathrow.
Package holiday company Jet2 has said that it will only be restarting its “flights and holiday programme” from June 17.
It said: “In view of the ongoing uncertainty caused by the Covid-19 pandemic…[for] customers travelling before this date, unfortunately your flights and holidays will not be operating. We will be contacting all customers to discuss their options.”
Competitor budget airline EasyJet has so far not made any official statement about its plans for the summer season.
Yet, EasyJet has recently launched a “winter sale”, with seats on “thousands of flights to top destinations across Europe for just £29.99”, to “help customers affected by recent travel disruption”, it said.
Public funds row
Ryanair has said that it will challenge the payment of public funds to flag carrier competitor airlines, including Air France and Lufthansa. It claimed that €30bn have been paid, in what it called “selective state aid doping for flag carriers”.
Ryanair chief executive Michael O’Leary - who has said he has taken a 50% pay cut until at least March 2021 - has warned of turbulence ahead for the sector as a result of the funds, saying: “Prices are going to be incredibly low, which is good for consumers but bad for airlines.”
He accused flag carrier airline companies of being “subsidy junkies”, whose call for public funds forced Ryanair to compete “with both hands tied behind its back”.
Mr O’Leary has also said that the idea of taking the middle seat out of plane seat rows to help with social distancing - suggested by some - would be fruitless.
He said: “Taking out the middle seat in an aircraft achieves no social distancing. There’s less than two feet between the aisle and the window seats.
“What we are recommending, and what the aviation industry is moving towards, is temperature checks on passengers at the airport - so that anybody who has a temperature of 38 degrees is asked to go home and self-isolate.”
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