London’s Heathrow airport has reiterated calls for the UK government to introduce a Covid-19 testing programme as an alternative to quarantine for arriving passengers, while reporting a £471 million ($611 million) pre-tax loss for the first six months of the year.

“Today’s results should serve as a clarion call for the government – the UK needs a passenger testing regime, and fast. Without it, Britain is just playing a game of quarantine roulette,” says Heathrow chief executive John Holland-Kaye.

He argues that testing passengers for coronavirus when they arrive in the UK “offers a way to safely open up travel and trade”. The suggestion comes after the government abruptly removed Spain from its travel corridor list and reintroduced quarantine measures for arrivals from the country.

The UK’s current strategy of waiving quarantine restrictions for arrivals from certain countries with similar or lower Covid-19 infection rates “only covers about 30% of Heathrow’s markets”, says the airport’s operator.

Heathrow’s revenues fell 85% to £119 million in the second quarter of 2020 as passenger numbers plummeted 96%. The airport’s operator says it expects “a gradual recovery as countries reopen borders” but passenger volumes for the full year will be 60% lower than in 2019.

Heathrow has enough cash reserves to last until “at least June 2021 with no revenue”.