Australia's forthcoming tour of South Africa has been postponed due to an "unacceptable level" of risk posed by coronavirus.

The Baggy Greens were scheduled to fly out for a three-Test series later this month.

With the host country battling a second wave of Covid-19 and a new variant of the virus, Cricket Australia's interim chief executive Nick Hockley said health and safety is the "number one priority" and "can't be compromised".

"Due to the public health situation in South Africa, which includes a second wave and a new variant of the virus and, following extensive due diligence with medical experts, it has become clear that travelling from Australia to South Africa at this current time poses an unacceptable level of health and safety risk to our players, support staff and the community," Hockley said in a statement.

"This decision has not been made lightly and we are extremely disappointed, especially given the importance of continuing international cricket at this time, our valued relationship with CSA (Cricket South Africa), and our aspirations to compete in the inaugural ICC World Test Championship.

"However, we have been consistent since the start of the pandemic that the health and safety of our people is always our number one priority and unfortunately despite best efforts to agree a bio-security plan, the risks are simply too great at this time.

"As difficult and disappointing a decision as this is, especially for Justin (Langer, head coach), Tim (Paine, captain) and the team, we have a duty of care to our people and their health and safety can't be compromised."

Cricket South Africa said less than a fortnight ago that the tour would go ahead in March or April.

However, CSA's board chairman Zak Yacoob also warned that the unpredictability of the Covid-19 virus could cause plans to change.

England left South Africa in December without playing three scheduled one-day internationals after two members of the hotel staff tested positive for Covid-19.