British Airways (BA) has put thousands of its staff back on furlough because of delays to the restart of international travel.
BA had begun to bring people back ahead of the easing of restrictions on foreign holidays on 17th May.
But only a small number of countries have been put on the government's green list, meaning travellers do not have to quarantine on their return.
Moreover, official advice remains not to visit amber countries for leisure.
This has meant the travel industry is now almost at a standstill as the majority of people choose not to travel.
It is understood a large number of BA staff were already on furlough, but this change means many more will go back onto the government wage support scheme.
Many will go onto the flexible furlough scheme and work part time, in the hope international travel will recommence soon.
Those affected include management staff and those not linked to safety operations and plane critical roles. It is understood every layer of the business is affected.
A British Airways spokesperson said: "Like many companies we're using the furlough scheme to protect jobs during this unprecedented crisis.
"However, it's vital the government follows its risk-based framework to re-open international travel as soon as possible, putting more low-risk countries, like the US, on its green list at the next available opportunity."
Airlines burn through millions of pounds when not operating because of safety, maintenance and engineering operations, and this decision is thought to be an attempt to preserve cash.
Lack of certainty
Transatlantic operators BA, Virgin and American Airlines had hoped there would be an agreement between President Biden and Boris Johnson at the G7 to create an air corridor between the US & UK.
But the industry was disappointed last night to be told a taskforce would only start looking at recommendations.
The boss of Virgin Atlantic, Shai Weiss, said: "The creation of the Atlantic Taskforce is positive recognition of the importance of the UK-US travel corridor and a first step towards reopening the skies."
But he said the lack of a specific time frame for reopening travel meant airlines, businesses and passengers faced a lack of certainty.