Thirty-eight MPs have written to the chancellor calling for support of the aviation sector as it battles with the impact of the coronavirus pandemic.
Airlines bosses have been lobbying government to put in place special measures to help carriers going out of business as a result of the unprecedented hit to the travel industry.
Virgin Atlantic are understood to be one of the airlines seeking state aid while Iata has demanded urgent action from European governments to offer financial aid to carriers.
Norwegian Air has secured state support, and US carriers look set for $60bn in financial aid.
But chancellor Rishi Sunak, who has unveiled a series of measures to help businesses survive the coronavirus crisis, has so far ruled out any specific package for the sector.
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The MPs’ letter, seen by the BBC, said the impact of coronavirus on UK aviation had been “severe and truly unprecedented” and that markets which have severe travel restrictions in place account for 98% of passenger revenues globally.
“Restrictions have all but eliminated airline and airport revenue, but not costs, which are substantial and go far beyond solely wages,” it said.
“It remains unclear what the duration of the economic impact will be on the UK’s airlines and airports, who face a pressing challenge to survive.”
The MPs’ call was backed Airlines UK chief executive Tim Alderslade and Airport Operators Association boss Karen Dee in a joint statement.
They said they had put “countless cross-industry ideas on the table to help aviation through this” but that “the chancellor said in his letter this week he was open to discussing them, yet no discussion has yet taken place”.
“We are now entering the danger zone, and we urge government to change tack and start to engage on a sector-wide basis before it’s too late.”
The MPs said aviation supported some 1.6 million UK jobs and the sector would be essential to support the recovery of the wider UK economy once the crisis had passed.
They called on the chancellor to provide cash support where necessary, as well as taking measures to safeguard jobs and ease regulatory and tax burdens.
Last week, Sunak ruled out a general bailout of the sector but pledged to consider “bespoke support” for airlines as a “last resort”.
Leading carriers jointly submitted a series of requests for emergency funds, tax deferrals and credit guarantees last week, with Department for Transport (DfT) officials reportedly “stunned” to learn how rapidly airlines could run out of cash.
The government says its emergency business measures, including a Bank of England scheme for firms to raise capital and employee wage subsidies, are available for airlines.
Transport Secretary Grant Shapps has said he cannot rule out the state taking an ownership stake in UK airlines that have been battered by the impacts of the coronavirus outbreak.