The country’s finance minister Simon Birmingham warned that Australia’s borders would not be “flung open at the start of next year with great ease”.

Birmingham added that there were “uncertainties” around both the speed of the Covid-19 vaccine roll-out and the vaccines’ effectiveness on new variants of the virus, during an interview with The Australian.

Australia had previously hoped to reopen its borders to international visitors in October 2021.

Other Australian ministers have suggested that its borders will be initially reopened through bilateral “bubbles” with regional destinations such as Singapore, Japan and Vietnam.

Australia has already established a “Tasman bubble” quarantine-free travel corridor with neighbouring New Zealand in April.

But this has been disrupted by the discovery of two positive Covid cases in Sydney this week which has led to an initial 48-hour suspension of flights between New South Wales and New Zealand.