Video report by ITV News Business and Economics Editor Joel Hills
EasyJet, Ryanair, Virgin Atlantic and British Airways parent company IAG have warned of "significant cancellations" as airlines struggle to deal with travel restrictions and a drop in demand due to coronavirus.
Virgin Atlantic said in a statement a "sharp and continual drop in demand" would lead to 75 percent of their fleet being grounded by March 26 and 85 percent in April.
It said it would prioritise "core routes, depending on customer demand" and reduce daily flights by 80 percent by March 26.
ITV Business Editor Joel Hills reports on how airlines are responding to the coronavirus outbreak.
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EasyJet said the "majority" of its planes could be grounded in the future, while IAG revealed its capacity for April and May would be cut by "at least 75 percent," compared with the same period for 2019.
"European aviation faces a precarious future and it is clear that co-ordinated government backing will be required to ensure the industry survives and is able to continue once this crisis is over," EasyJet chief executive Johan Lundgren said.
"We continue to operate rescue and repatriation flights to get people home where we can, so they can be with family and friends in these difficult times.
Ryanair said in a statement on Monday it expected the "majority" of its European fleet to be grounded "over the next seven to 10 days."
It said by April and May seat capacity would be reduced by up to 80 percent, and "a full grounding of the fleet cannot be ruled out."
IAG Chief Executive Willie Walsh - who was due to step down next week - postponed his retirement plans to provide stability to the company.
“We have seen a substantial decline in bookings across our airlines and global network over the past few weeks and we expect demand to remain weak until well into the summer," he said.
“We are therefore making significant reductions to our flying schedules. We will continue to monitor demand levels and we have the flexibility to make further cuts if necessary."
Transport Secretary Grant Shapps told ITV News Economics Editor Joel Hills he was exploring various options to help the industry and said he was holding an "aviation summit" this week to work out the best course of action.
He noted a request from Virgin Atlantic for a £7.5bn bailout to save the whole industry, but he said other airlines "disagree with that".
He said: "We've been looking at different ways to assist but it's noticable that the requests actually vary about what's required at this stage."
He said airlines are at the "forefront" of the coronavirus outbreak, adding, "it's very serious, there's no other way to describe it, I mean this is an international crisis".
Transport Secretary Grant Schapps speaks on cancellations made by major airlines amid the coronavirus outbreak.
He admitted there was "certainly a risk" that airlines could go bust "if nothing were done" but he claimed the government is "will try to stand by our businesses to make sure that good strong businesses can survive".
He cited his work on cancelling ghost flights - journeys airlines were forced to carry out, even if they have no passengers, due to scheduling commitments - as one way the government is helping airlines.
He also said HMRC was being more flexible in order to help companies by offering them a 'time to pay', but he did not commit to any further contingency plans.
The move comes as the Foreign Office updated its list of countries to which it advises against "all but essential travel."
Popular destinations including the United States, Spain, Italy and Cyprus have all been included on the list.
On Saturday, carrier Jet2 dramatically forced five flights en route Spain to turn back in mid-air after Spain introduced new coronavirus measures.
It's also reduced its flight schedule and cancelled all flights to mainland Spain, France, Italy, and other countries.
EasyJet said it was taking "every action" to cut costs, and insisted it "maintains a strong balance sheet," including £1.6 million cash and £405 million credit facility.
IAG said it was also cutting costs but added it had a "total liquidity" of 9.3 billion euros (£8.4 billion).
"IAG is resilient with a strong balance sheet and substantial cash liquidity," Chief Executive Willie Walsh said.
Ryanair also said in a statement it was taking "immediate action" to improve cash flow and reduce costs, including freezing recruitment and "significant reductions" to working hours and payments.
Virgin Atlantic said it was taking "immediate action" to reduce its costs, and was asking staff to take eight weeks unpaid leave over the next three months to "drastically reduce costs without job losses."