Australia would further shorten the wait time for people to receive their Covid-19 booster shots, Health Minister Greg Hunt said on Friday, as the country grapples with record infections fuelled by the Omicron variant.

Booster shots will be offered from Jan 4 to everyone over 18 who had their second shot four months earlier and the interval will be again reduced to three months by the end of January.

"These dates have been set out of an abundance of caution to give Australians early continued protection," Hunt said during a media conference in Canberra.