Australian Olympic Committee (AOC) chief executive Matt Carroll believes holding the Games in 2021 remains tough as his nation's athletes prepare for a postponed event.

The International Olympic Committee (IOC) announced on Sunday it had set a four-week deadline to make a decision on the Tokyo Games.

Canada have decided not to send athletes to an Olympics this year, while Australia are preparing for a Games in 2021.

The AOC said last week the Olympics would either go ahead or be cancelled, but Carroll feels a postponement is possible, although tough.

"It remains difficult hence why their decision is they will come back to us within the month," Carroll told a news conference on Monday.

"Moving the world's biggest sporting event, it involves so many people, so many sports, not just athletes, but also the world's media, sponsors, the rest.

"It's not easy to do, it remains challenging, but the IOC decided they have to look at that as well."

There have been more than 339,000 cases of coronavirus worldwide, with more than 14,600 deaths.

Carroll said while athletes wanted to compete, the uncertainty globally meant it was best to look towards 2021.

"The AOC executive met this morning and considered all the parts – both the IOC's decision, the government [travel] measures and most importantly, our athletes," he said.

"The decision is that they unanimously agreed that the Australian Olympic team could not be assembled in the changing circumstances both here and abroad.

"We have to look after not only just our athletes and officials, but also their families, who were feeling concerned for their sons and their daughters.

"With these travel restrictions in place by the government which we respect and understand and we understand they need to keep Australians safe, combined with the decision of the IOC, we've decided to plan towards the hosting of a Games in 2021 in Tokyo.

"I understand that's a situation which the Tokyo government and TOCOG [Tokyo Organising Committee of the Olympic and Paralympic Games] will look at with the IOC over the coming month."