The Australian Olympic Committee (AOC) will start vaccinating Tokyo-bound athletes against Covid-19 next week using a private contractor to avoid burdening the public health system.

Around 100 South Korean athletes and coaches will get their first shots on Thursday, while around 500 others will be inoculated by the first week of May before they travel to Japan for the Games, Yonhap said, citing the Korean Sport and Olympic Committee (KSOC), Yonhap news agency reported.

The Australian government on Tuesday approved the vaccination of more than 2,000 athletes, coaches and officials nominated by the AOC and Paralympics Australia before they travel to Japan for the Olympics and Paralympics.

"Planning is now full steam ahead," chief executive Matt Carroll told reporters in Sydney.

"The management of the vaccination will be done by the AOC with our partner Aspen Medical so there's no load on the public system whatsoever. And we'll commence that next week."

While Australia has been highly successful at containing the coronavirus, it has been relatively slow at rolling out the vaccine compared to other developed nations.

Sports Minister Richard Colbeck on Wednesday defended the decision to give the Olympians access to the vaccine when some people at higher risk have not received their shots.

"We've always prioritised the vulnerable, and that's why they were the first that were given access to the vaccines, and that process continues," he told ABC radio.

"But it was always anticipated that there would be overlaps in the various stages. (We included) the athletes and support staff in the rollout, in support of the athletes being able to compete (as) safely as possible in the Games."

Nearly 2.7 million South Koreans out of a population of 52 million have received their first vaccine dose, bringing the vaccination rate to just above 4%. The low rate compares with a 41% rate in the United States, according to Reuters data.

Covid-19 vaccinations are not mandatory for participation in the Olympics, but they are recommended.

Tokyo, Osaka and two other Japanese prefectures last week entered a state of emergency after a resurgence of the virus.

Carroll said he remained convinced that the Olympics, which were postponed from last year, would still go ahead as scheduled from 23 July to 8 August.

"(Japan) really want to host the games, otherwise they wouldn't be there," he added.

"They want to do it for the athletes of the world so they can come and compete. It's an opportunity for the world to connect virtually and celebrate all the power of sport. Those are the reasons why everyone is committed to making it happen, and it will happen."