Ryanair is not currently expecting to operate flights in April or May as a result of the coronavirus outbreak.
The company has already said it expects to ground most of its flights from tonight - although it will continue to assist with rescue flights for stranded citizens and helping to transport essential supplies such as medicine and protective equipment for healthcare workers.
In a letter to customers today, the airline's CEO Michael O'Leary said nobody knows how long the shutdown will last.
A message to all Ryanair Group customers: pic.twitter.com/nzDhDt9jz4
— Ryanair (@Ryanair) March 24, 2020
However, he suggested the experience from China indicates it could take three months for the virus to be "contained and reduced".
He said: "We do not expect to operate flights during the months of April and May at this time, but this will clearly depend upon Government advice, and we will in all cases comply with these instructions.
"While the immediate future is uncertain, it is important to remember that, like all pandemics, this crisis will pass."
He pledged that the company will do "everything we can" to support governments, staff and customers, adding that they will work to keep all their aircraft and crew operation so that the airline can return to flying "when Europe defeats this COVID-19 pandemic".
Ryanair is one of many global airlines to have significantly reduced services in recent days, with Emirates 'suspending most passenger flights' from tomorrow.
Aer Lingus has reduced its schedule of flights to many European and North American destinations.
Meanwhile, the Irish embassy in the US is encouraging any Irish citizens still there to return to Ireland now due to commercial flights becoming more limited.