King Charles III became the British monarch after his mother's death. As the British monarch, he is also the head of state of Australia, New Zealand, and 12 other Commonwealth countries outside the United Kingdom, though the role is largely ceremonial.

Australia's new $5 banknote will not feature Britain's King Charles III, but will rather honour "the culture and history" of Indigenous Australians, the country's central bank announced Thursday.

The new design will replace the portrait of Her Majesty Queen Elizabeth II on the current $5 note, the Reserve Bank of Australia (RBA) said in a statement.

Billions of banknotes and coins around the world are in the process of being replaced following the Queen's death last September, which reignited debates about Australia's future as a constitutional monarchy.

"This decision by the Reserve Bank Board follows consultation with the Australian government, which supports this change," the bank continued in its statement.

"The Bank will consult with First Australians in designing the $5 banknote. The new banknote will take a number of years to be designed and printed. In the meantime, the current $5 banknote will continue to be issued. It will be able to be used even after the new banknote is issued."

First Australians refers to Australia's Indigenous population, or First Nations people, made up of Aboriginal and Torres Strait Islanders. They lived in the country for at least 65,000 years before British colonisation, according to recent estimates, and together they make up about 3.2% of the country's population of 25 million people.

The A$5 bill is the only Australian banknote to carry the image of a British monarch. The late Queen appears on the country's coins as well, and officials have also said coins with her image will remain legal tender "forever".

King Charles III will continue to be featured on coins, which the Royal Australian Mint is expected to start producing "in the second half of this year," Andrew Leigh, the assistant minister for competition, charities and the treasury, said.

Though the RBA has said it does not yet have a date for when it will reveal the new five dollar note design, the mint has said it expects to unveil the design of the first King Charles coins early this year.

The RBA's decision was welcomed by Aboriginal politicians and community leaders.

"This is a massive win for the grassroots, First Nations people who have been fighting to decolonise this country," said Lidia Thorpe, a Greens senator.