On Monday, Aboriginal Senator Lidia Thorpe labeled Britain's Elizabeth II a "colonizing" queen as she mockingly vowed allegiance while taking the oath of office.

Greens senator Thorpe lifted her right fist in a Black Power salute as she vowed to serve the 96-year-old monarch, who remains Australia's head of state.

"I sovereign, Lidia Thorpe, do solemnly and sincerely swear that I will be faithful and I bear true allegiance to the colonizing Her Majesty Queen Elizabeth II," she said before being rebuked by a Senate official.

Watch the moment Lidia Thorpe had to take a second oath after saying “colonising” before “Queen Elizabeth II” pic.twitter.com/cnRJ2YEjcb

— Leonardo Puglisi (@Leo_Puglisi6) August 1, 2022

"Senator Thorpe, Senator Thorpe, you are required to recite the oath as printed on the card," said the chamber's president Sue Lines. After reciting the pledge as required, Thorpe wrote on Twitter: "Sovereignty never ceded."

My questions about Labor’s Voice to Parliament included Sovereignty, Treaty and Free, Prior and Informed Consent as defined in the United Nations Declaration on the Rights of Indigenous People (which Labor supported in the last parliament).

Sovereignty 👇🏾 pic.twitter.com/D9MpmEdMac

— Senator Lidia Thorpe (@SenatorThorpe) August 1, 2022

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For more than a century, Australia was a British colony, during which thousands of Aboriginal Australians were slain and entire communities were uprooted. The country achieved de facto independence in 1901 but never achieved full republic status.

In 1999, Australians narrowly rejected deposing the Queen, amid a debate over whether her replacement would be chosen by members of parliament rather than the general population.

Most Australians support becoming a republic, according to polls, but there is little agreement on how a head of state should be chosen.

The topic was reignited following the election of famous republican Anthony Albanese as Prime Minister. He quickly appointed the country's first "minister of the republic."

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"I do support a republic," Albanese told CNN on Sunday but added that another referendum would have to wait until after a promised referendum on giving Aboriginal Australians an institutional role in policymaking.

"Our priority this term is the recognition of First Nations people in our Constitution," he said.

Thorpe has also advocated for historical truth and reconciliation, as well as a "treaty" that would officially recognize Aboriginal historical ownership of the land.