The men, at least two of whom appear to have worked for Qantas subsidiary Jets Transport Express, attempted to bring 100kg of cocaine with an estimated street value of $40 million into the country on a cargo flight from Johannesburg.

The test, conducted last month by Royal Australian Air Force F/A-18F Super Hornets off the coast of California, with support from the United States Navy, confirmed that the LRASM is now ready for operational service.

While no Qantas services have been affected, six Jetstar flights on Friday morning were cancelled and two morning Virgin Australia services – to Brisbane and Melbourne – were pushed back to the afternoon due to potential impact from the ash cloud.

Heathrow, the largest of London’s six commercial airports, will remain closed until at least 11:59pm local time on Friday, causing havoc in the surrounding airspace. At least two Qantas flights in the air have been forced to divert, while others set to depart Heathrow today will also be affected.