Designers of the Indigenous voice to parliament referendum hope a meeting with Opposition Leader Peter Dutton will help them clinch the support of the Liberal Party.
Mr Dutton will discuss the proposal of constitutional recognition with the government's referendum working group on Thursday.
UNSW Constitutional Law professor Megan Davis, who is also the Uluru Dialogue co-chair, said she wanted to help clarify the mechanics of the voice and why it was important.
"Our hope is that Mr Dutton and his party room support First Nations Peoples and help bring the whole country together to make this important constitutional change," she said.
Bipartisan support has historically been needed for referendums to succeed.
The Nationals are opposed to the voice and Mr Dutton is weighing up whether the Liberals should also take a "no" stance or allow MPs a conscience vote.
Calare MP Andrew Gee quit the Nationals in December and will sit as an independent because the party decided against backing the voice.
Assistant Indigenous Australians Minister Malarndirri McCarthy on Wednesday said the government needed to reach out to conservatives across Australia and help them feel "unafraid" to make the decision to vote for change.
Prime Minister Anthony Albanese said the government planned to introduce legislation to parliament in March to set up the referendum.
He said if the bill passed by the end of June, it meant Australians could vote in the referendum as early as August, or as late as November.
Mr Albanese called on Mr Dutton to support the voice.
"I hope he goes and meets with the referendum working group ... with an open mind and, importantly as well, an open heart," he said in Perth.
