The Northern Territory government has declared the Greater Brisbane area a coronavirus hotspot, restricting travel to the Territory.
Anyone arriving from Brisbane from Friday will be required to enter mandatory supervised quarantine.
Acting Chief Minister Nicole Manison said that would also impact people who arrived on a flight from Brisbane on Friday morning and to those on two more flights on their way.
People on those flights will not be required to pay the $2500 quarantine fee and will also be offered the option of an immediate and free return flight.
"I know this is very difficult for those people have been impacted and will be impacted," Ms Manison said.
"But I've just got to stress, this is about keeping Territorians safe."
The new restrictions also apply to anyone arriving from Brisbane by road, with a 12.30pm (CST) deadline set to avoid the quarantine fee.
They follow the three-day lockdown ordered for Brisbane by the Queensland government after a cleaner at a quarantine hotel was diagnosed with the more contagious UK variant of COVID-19.
