The Heathrow-Darwin-Melbourne flight had been due to revert to its London-Perth-Melbourne schedule in April, but Qantas said “ongoing uncertainty” around the reopening of the Western Australian border had delayed this again “until at least June 2022”.

The airline’s other UK service is to Sydney, which normally operates via Singapore, but testing requirements for transit passengers also mean this service is operating direct to Darwin before continuing to Sydney.

Qantas said: “To streamline transit arrangements for passengers, Qantas will also continue to operate the Sydney to London flight via Darwin instead of through Singapore until June 2022.”

Qantas Group chief executive Alan Joyce said the Northern Territory had the added bonus of capitalising on pent-up international inbound travel demand.

“This extension through to at least mid-June means the Top End has several months to properly leverage the opening up of Australia’s borders to all tourists. It’s a great opportunity to encourage thousands of visitors to stop off in Darwin to see what the NT has to offer.”

Qantas currently operates daily flights from Melbourne and Sydney to London via Darwin on the Boeing 787 Dreamliner.