SYDNEY: The Australian Olympic Committee (AOC) has labelled the government of South Australia "cruel and uncaring" for imposing an extra two-week quarantine for athletes returning via Sydney from the Tokyo Games, meaning a 28 days of quarantine in total.

The additional quarantine requirement for athletes currently isolating in Sydney, the capital of New South Wales, comes on top of the two weeks mandated for all arrivals from overseas.

"Due to the high risk of the Delta strain of COVID-19 in NSW, anyone travelling from New South Wales must undertake 14 days quarantine upon entry into South Australia," the state said in a statement.

The AOC said South Australia had turned down its request for an exemption from the extra quarantine period.

"While other countries are celebrating the return of their athletes, we are subjecting ours to the most cruel and uncaring treatment," AOC Chief Executive Matt Carroll said in a statement on Wednesday.

"They are being punished for proudly representing their country with distinction at the Olympic Games."

The AOC said 56 members of the Australian Olympic team were returning to South Australia 16 were already undergoing quarantine in Sydney.

"Not only are our Olympians fully vaccinated, but they have also been living in a highly controlled bubble in Tokyo, taking the utmost precautions -- tested daily over many weeks," said Carroll.

"We have received no explanation as to why our application on behalf of these athletes has been rejected."

The Australian Institute of Sports' Chief Medical Officer David Hughes said the extra quarantine period could not be scientifically justified and posed a significant risk to the physical and mental wellbeing of individuals affected.

Through a combination of strict travel and border controls and snap lockdowns, Australia has fared better than many other developed countries during the pandemic, recording fewer than 37,000 COVID-19 cases and a death toll under 1,000.