Graeme Smith has admitted Cricket South Africa (CSA) was left "extremely disappointed" with the decision taken by Australia to pull out of their upcoming tour.

A three-Test series was scheduled to take place in March, but Cricket Australia (CA) announced on Tuesday that those plans had been shelved due to the public health situation in South Africa amid the ongoing coronavirus pandemic.

The country was dealing with over 10,000 positive COVID-19 cases a day at the start of January and while that number has since dropped considerably, there is also a new variant of the virus.

However, having done all possible to appease safety concerns and establish protocols so the tour could take place as planned, CSA director of cricket Smith revealed the frustration at the late cancellation.

"We are extremely disappointed by the decision of CA," former Proteas captain Smith said. "CSA has been working tirelessly in recent weeks to ensure that we meet every single expectation of CA.

"This was set to be the longest tour in a BSE (bio-secure environment) comprising a three-match Test series that was scheduled to begin with Australia's arrival later in the month. So to be informed about the CA decision at the eleventh hour is frustrating."

Dr Shuaib Manjra, chief medical officer for CSA, explained how the organisation had done everything possible during the planning stage, including proposing protocols to their Australian counterparts that were "unprecedented".

The cancellation has ramifications for the inaugural ICC World Test Championship, too. New Zealand are now certain to be playing in the final later this year, where they will go up against either England, India or Australia.

Pholetsi Moseki, acting CEO for CSA, said: "It is indeed sad that after all the engagements and effort made to ensure a secure visit by our Australian counterparts, the tour has been derailed.

"CSA has incurred significant costs related to the planning stages and the cancellation of the tour represents a serious financial loss."

South Africa are currently on tour in Pakistan, with the second of two Tests set to start on Thursday in Rawalpindi.

They will also play a three-match Twenty20 series against their hosts - with all the white-ball fixtures to be staged in Lahore - before returning home in the middle of February.