Australia's prime minister and other political leaders have laid wreaths at Parliament House to honour the late Queen Elizabeth II.
Prime Minister Anthony Albanese, Governor-General David Hurley and Opposition Leader Peter Dutton marked the monarch's passing with a ceremony at the Queen's Terrace on Saturday morning.
The wreath-laying comes more than 30 years after the monarch opened the new Parliament House in 1988, which included unveiling a statue of herself.
The Queen's eldest son became King Charles III immediately after her death in the early hours of Friday morning at Balmoral Castle in Scotland.
In a speech overnight, the new king promised to serve the crown's realms and territories across the world with "loyalty, respect and love".
"As the Queen herself did with such unswerving devotion, I too now solemnly pledge myself," King Charles said.
Shortly after the wreath-laying, Mr Albanese pointed to the King's comments on the "affection, admiration and respect" the Queen inspired, which became a hallmark of her reign.
"That's why so many Australians have made moving tributes and are mourning this enormous loss," he said.
"She was a constant reassuring presence with her compassion, her decency, her commitment to service which is an absolute inspiration."
Mr Dutton said the King had shown he was continuing with the same selfless spirit as his late mother.
"That continuity is an essential part and King Charles had demonstrated his commitment to his country and to the realms," he said.
"His dedication to the throne will mean an enormous amount, not just to the United Kingdom but to Commonwealth countries as well."
Across the country, Australians continue to mark the passing of the Queen, with hundreds of people laying flowers at Government House in Sydney and Melbourne.
NSW Police will ramp up their presence at memorial sites in Sydney, including the Royal Botanic Gardens and state parliament.
On Sunday, a Proclamation of the King ceremony will be held outside Parliament House in Canberra, followed by a 21-gun salute.
This will be echoed by similar proclamation ceremonies by state governors.
On Friday evening, a 96-gun salute took place in the federal parliament forecourt - one round for each year of the life of the Queen, who reigned for 70 years.
The sails of the Sydney Opera House, which Her Majesty opened in 1973, were illuminated in her honour. So too were monuments in other cities, and flags were flown at half mast around the nation.
Since news broke of the monarch's passing Australians have gathered to lay flowers, sign condolence books and raise a glass to the Queen.
"Now she's gone, we feel a little older, and we feel that loss," said John Myers of Hawthorn in Melbourne's east.
"She had so much humour and dignity and love for her country and the Commonwealth," Melburnian Pettifleur Berenger told AAP.
"She was the grandmother of the Commonwealth," Sydneysider Oliver Pasusuwin said.
Mr Hurley and Mr Albanese will fly to London on Thursday to attend the Queen's funeral, the date for which is still to be confirmed.
No official mourning period has been declared in Australia, unlike in the UK which has begun 10 days of mourning.
Queensland and federal parliaments have suspended their sitting days next week, while NSW, Victorian and West Australian MPs will sit on Tuesday to hear condolence motions.
Also this weekend, the AFL and NRL will observe one minute's silence at all games on Saturday and Sunday, with one-minute silences also expected at cricket and soccer matches on Sunday.
© AAP 2022