Queensland's PCR test requirement has "destroyed" the ACT's testing regime and must be urgently scrapped, Canberra Airport says.
Canberra Airport chief executive Stephen Byron has written to the Queensland government, warning COVID-19 cases were going undetected in the ACT because interstate travellers were clogging up the territory's testing system.
ACT Health Minister Rachel Stephen-Smith has also called for rapid antigen tests to replace PCR tests as a condition of entry across Australia, arguing they are accurate enough to screen interstate travellers.
Queensland currently requires travellers from the ACT to test negative via a PCR test within 72 hours of arrival.
The ACT's three testing sites open on Monday were at capacity by midday, as interstate travellers joined close contacts and symptomatic Canberrans in a rush to get tested.
The territory's contact-tracers have advised they were days behind as they struggled to meet demand, with many Canberrans forced to assess whether they were a casual or close contact themselves.
The ACT government estimated interstate travellers accounted for roughly half of people undergoing PCR tests in the territory.

South Australia abruptly scrapped a PCR test requirement for interstate travellers on Boxing Day, accepting a negative rapid antigen test to ease testing queues across the country.
ACT Health Minister Rachel Stephen-Smith described the decision as a "good move in the right direction", which would enable the territory to target its health response.
She said rapid antigen tests should replace PCR tests as a condition of entry across Australia.
"Where they are useful, particularly when they're taken over a number of days and repeatedly, is for that screening purpose," she said.
"So for those jurisdictions who are just looking for a bit more security around the people who are entering the state, they have a high enough accuracy rate to be really useful for that purpose."
Mr Byron has called on Queensland to follow suit, warning interstate travellers were clogging the territory's testing regime and preventing authorities from uncovering COVID-19 cases.
And with the virus already spreading quickly in Queensland, which recorded 784 cases on Monday, he said there was no justification for the requirement.
ACT Health has warned PCR test results were often taking longer than 48 hours, and Mr Byron warned interstate requirements had "destroyed the ACT testing and containment strategy".
"They should revert to rapid antigen tests urgently as they are doing real damage to Canberrans," he said.
"Testing clinics are under unreasonable pressure. No one should have to wait so long for a test. Travellers and families should not be put under this sort of stress.
"Overall, Queensland's rules are causing lots more cases of COVID to be undetected in the ACT.
"It has to stop. Urgently."
Prime Minister Scott Morrison last week urged states to accept rapid antigen tests - less accurate than PCR tests, but with a quick turnaround - as a condition of entry.
Tasmanian Premier Peter Gutwein on Monday confirmed the state's PCR requirement would remain "for the time being", but was considering options.
"We'll have more to say on this, I'll speak later in the week about what the requirements will be in terms of our borders, as we approach the New Year," he told reporters.
And Queensland has repeatedly stated it would not make the shift until the New Year at the earliest, and only after being given the green light by health authorities.
Given huge wait times for tests in NSW and Victoria, often exceeding 72 hours, that has left some travellers forced to isolate even after arriving in Queensland.
It comes as health experts call for federal and state government to provide rapid antigen tests free-of-charge, arguing they would provide an added layer of protection and ease wait times.
NSW was exploring ways to provide the test some time in the New Year.