'I have spent my entire life fighting for justice.' Senator Lidia Thorpe has quit the Greens.

Victorian senator Lidia Thorpe has quit the Greens party and will move to the crossbench, due to disagreeing with her colleagues on the topic of Indigenous sovereignty.

The First Nations senator confirmed the news to reporters in Canberra on Monday, the first day of parliament for the year.

"This country has a strong grassroots Black sovereign movement, full of staunch and committed warriors, and I want to represent that movement fully in this parliament. It has become clear to me that I can't do that from within the Greens." 

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Senator Thorpe said her new independence would enable her to better fight for First Nations justice and sovereignty.

"I'm ready for what comes next in the fight for a future where our kids are with their families, where our people are not killed in custody, where the chains that the system wraps around our people are lifted. I will be able to speak freely on all issues from a sovereign perspective without being constrained by portfolios and agreed party positions."

Senator Thorpe said a Voice to Parliament was at odds with what parts of her community had told her but noted she had not reached her final position on the constitutional change, which is expected to be put to a referendum later this year.

Senator Thorpe said her issue with the Voice to Parliament proposal was the lack of guarantee that Indigenous sovereignty would not be ceded. Her announcement means the Greens will be reduced from 12 senators to 11 and the government will have an additional independent crossbencher to negotiate with. She will however continue to vote with the Greens on climate issues in the Senate.

Crossbencher Jacqui Lambie said it "took guts" and being independent was the best way to represent your community.

"No party lines, no talking points," the Tasmanian senator tweeted. "Every time the crossbench grows, it's a good thing. Representation gets more representative. Love to see it."

'There is a black sovereign movement out there that no-one wants to listen to, so I will be their voice.' Lidia Thorpe leaves the Greens for crossbench.
Read more: https://t.co/dvdJR4NSWI pic.twitter.com/dE3MimHS6L

— SBS News (@SBSNews) February 6, 2023

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— Senator Lidia Thorpe (@SenatorThorpe) February 6, 2023

Greens leader Adam Bandt told reporters he would have liked Senator Thorpe to stay in the party but respected her decision.

"I confirmed that, under the Greens' constitution, she had the ability to vote differently," he told reporters in Canberra in relation to the voice.

Bandt said he and a lot of party members and voters were saddened by the outcome.

"She's made that decision and she's explained her reasons for doing it. And we just have to deal with the facts as we find them," he said.

The minor party is expected to come to a decision on the voice within days.

Prime Minister Anthony Albanese, constitutional experts and the referendum working group have said the voice would have no impact on First Nations sovereignty. Albanese said the Voice to Parliament should be above politics.

"We need to get the detail right and there would be a process, as well as that parliamentary debate about the legislation, and I'd want to get as much agreement as possible," he told reporters in Canberra. 

"I want this to be a long-term reform to benefit Indigenous Australians, to help close the gap."

He continued: "The call for an Indigenous recognition in our constitution and consultation on matters that affect them will not have an impact on most people's lives, but it might just make some people's lives, some of the most disadvantaged people in our country, better."

The question people will be asked at the referendum on the Voice will be known by the end of June.

— With AAP.

Feature Image: Getty.