Former Indigenous Australians minister Ken Wyatt has quit the Liberal Party in outrage at its decision to officially oppose the Voice to parliament.

“I still believe in the Liberal Party values but I don’t believe in what the Liberals have become,” Mr Wyatt told The West Australian on Thursday.

“Aboriginal people are reaching out to be heard but the Liberals have rejected their invitation.”

Mr Wyatt was a member of the referendum working group which helped shape the final proposal being put to the public at the poll later this year.

He was also a member of cabinet in Scott Morrison’s government when a previous version of the Indigenous voice was being considered.

Mr Wyatt served as a minister from 2019 to 2022 before losing his WA-based seat at the last federal election.

His decision came hours after outspoken Liberal backbencher Bridget Archer said she had also considered quitting the Liberals over their position on the Indigenous voice.

But she said like-minded moderates kept her on the opposition benches as she fought for the party’s return as a “credible alternative” to the government.

“Sometimes I do consider [resigning] and then I consider the people in the Liberal Party that share my views … people that I consider to be like-minded Liberals,” she told ABC Radio National.

“I stay because I know that I am not the only person that thinks that way and I stay because I think the Liberal Party is at a crossroads.”

Following a two-hour meeting in Canberra on Wednesday, the Liberal Party agreed to support the constitutional recognition of Indigenous people, but not an enshrined voice to parliament and executive government.

Mr Wyatt was the first Indigenous person to be elected to the federal House of Representatives. He has long urged his former party colleagues and Coalition colleagues to educate themselves on the role of the Voice and support the historic proposal.

Earlier this week, he renewed those calls ahead of the party room meeting where the decision to oppose the Voice was made.

• Liberals commit ‘Judas betrayal’ in opposing Voice

In December 2021, Mr Wyatt, then Indigenous Australians Minister in Scott Morrison’s cabinet released a 272-page report on the Indigenous Voice co-design process.

Late last year, after the federal Nationals said they would formally oppose the Voice, he urged its MPs to read the report.

Ms Archer said there was a perception that the Liberal Party was racist and positioning itself adjacent to racist views in the ‘no’ campaign would enhance that perception among voters.

“There needs to be a commitment from the party, a decision to learn the lessons from the last election quickly, to move forward purposefully into the future [and] to evolve,” she said.

She said she was concerned about Opposition Leader Peter Dutton confirming he would actively support a ‘no’ campaign on the voice.

“We’ve already seen warnings from the Racial Discrimination Commissioner about the rhetoric that we’re seeing from a ‘no’ campaign,” she said.

“It is going to be an unpleasant and divisive road ahead if that continues … and we should be seeking to not even want to be adjacent to that sort of language and that sort of posturing.

“That’s the problem we face ahead … in prosecuting a no campaign. How do you do that in a united way and not be divisive? I’m not sure that is possible.”

Ms Archer said the decision to oppose the Voice was another example of the Liberals not presenting a credible alternative to government in opposition.

Former Liberal leader John Hewson said Mr Dutton had failed to learn any lessons from the party’s recent historic loss at the Aston by-election.

He said Mr Dutton would likely think his ‘no’ stance would be the critical blow for the Indigenous voice.

“I’m very concerned as to where the Liberal Party’s ended up, certainly on the Voice they’re on the wrong side of history,” Dr Hewson told ABC Radio.

“Dutton’s been sort of dancing around the issue trying create the circumstances in which he could take a ‘no’ position.”

Dr Hewson said the Aston result, where the government won a seat from the opposition at a by-election for the first time in more than 100 years, showed the Liberals needed to change its approach.

“One of the messages of Aston was that people are sick and tired of politicians playing games, just scoring points on each other on the negativity of the opposition,” he said.

“Just to be negative on (the voice) is not in the national interest. It is in our national interest to come to grips with our history and to demonstrate to the world that we’re on top of it.”

Former deputy Liberal leader and Aboriginal affairs minister Fred Chaney said the decision to oppose the Voice was a “massive disappointment”.

“I’m sadly not surprised because I think they’re desperately looking for political advantage on this, instead of treating it as a serious issue, and I think it’s a big sell-out of their own legacy,” he told ABC Radio.

“They are playing politics with this, I think they’ve been doing that for months now. This whole question about more detail has been a cover for the desire to oppose it.”

-with AAP