The Governor-General will officially proclaim King Charles III as Australia’s new head of state following the death of Queen Elizabeth II.
Prime Minister Anthony Albanese will meet with ministers, acting as the Executive Council, on Sunday morning to formally recommend Sir David Hurley to issue the proclamation.
They will then travel to Parliament House for a formal ceremony, followed by a 21 – gun salute, to officially acknowledge King Charles III as Australia’s new sovereign.
It follows the UK’s proclamation at St James Palace on Saturday evening, Australian time.
Flags across the nation, which have been lowered in mourning for the Queen, will fly full-mast after the proceedings. They will be lowered to half-mast again after dusk.
Sunday’s ceremony will be the first time a proclamation has been read at Australia’s current Parliament House.
The Australian proclamation of Queen Elizabeth II took place at Canberra’s Old Parliament House.
Proceedings will include a band performing the Australian anthem and God Save the King.
The Governor-General and Mr Albanese are expected to fly to London on Thursday to attend the Queen’s funeral on September 19.
As Australia continues to observe the 14-day mourning period for the late monarch, the government has confirmed a “one-off” public holiday the National Day of Mourning — to be held on September 22 when the Prime Minister returns from the Queen’s funeral.
On Saturday evening, Parliament House was lit up with projections of the late Queen, to honour her death.
Earlier, leaders gathered at the Queen’s Terrace to lay floral wreaths at the foot of parliament’s statue of the late monarch, which her majesty unveiled on 9 May 1988 while visiting Australia to officially open the new building.
The floral tributes mark the continuing Australian commemoration of the Queen after she died in her Scotland castle at age 96.