Lidia Thorpe is demanding King Charles make reparations to indigenous people for slavery.
The independent federal senator co-signed a letter from representatives of 12 countries demanding the wealth of the Crown be divided up among indigenous people impacted by colonialism.
The letter also demanded the King return the remains of Indigenous people and cultural artefacts.
“We stand united in engaging in a process to right the wrongs of the past and to continue the process of decolonisation,” the letter said.
Nova Peris, the first Indigenous woman elected to federal parliament and co-chair of the Australian Republic Movement, also signed the letter.
Thorpe, who has said she wants to meet with King Charles, said neither the Crown nor the Australian Government had “been held to account” for colonisation.
“The British monarchy oversaw the oppression of First Nations peoples in British colonies all over the world,” she said.
“The horrific impacts of British colonisation, including the genocide of our people, theft of our land and denigration of our culture, are still felt today.
“The genocidal project that commenced in 1788 still continues and neither the British Crown nor the Australian government have been held to account for the crimes they have committed.”
Thorpe said she wanted Australia to become a republic but “we have unfinished business to settle before this can happen”.
“A Republic that hasn’t resolved the injustices of terra nullius continues the violent legacy of colonisation, and this is why the federal government must commence Treaty negotiations at a national level,” she said.