Heathrow has recorded a further £329 million loss for quarter one of 2021, as only 1.7 million passengers travelled through the airport, down 91 per cent compared to the first three months of 2019.
The new figure brings total losses since the start of the pandemic to nearly £2.4 billion at the airport.
Cargo volumes are also down 23 per cent on 2019, underlining how a lack of flights impacts UK trade with the rest of the world.
Officials said, while underlying demand for travel remains strong, continuing uncertainty over government policy has seen Heathrow reduce its passenger forecast for the year to a range between 13 and 36 million, compared to 81 million in 2019.
As vaccinations are rolled-out and Covid-19 levels fall, restarting travel to markets like the US will be critical to the economic recovery of the UK, the airport added in a statement.
Heathrow chief executive, John Holland-Kaye, said: “These results show how Covid-19 has devastated the aviation sector and British trade.
“Restarting international travel from May 17th will help to kickstart the economic recovery, allowing exporters to get their goods to market, as well as reuniting families who have been separated for over a year.
“Heathrow is gearing up for the recovery.
“By acting early to cut costs and protect cash, we have put ourselves in a strong financial position to weather the storm and are ready to welcome back passengers, while keeping them safe.”
Heathrow said decisive management action had seen the airport reduce cash burn by 50 per cent versus quarter one of last year.