“If we can get amendments to make sure it’s as fair as we can make it,it may well be I vote yes ... particularly in relation to recognition,” he said.

“We are not throwing the baby out with the bathwater,we are still in the game.”

Recent polling shows support for the Voice is softer in Queensland than in other states. Entsch said he believed it was because more people were living in regional and remote parts of the state and had a higher level of awareness of issues facing remote communities.

Birmingham,who as recently as February said he supported the Voice in principle,is now bound by the opposition’s position as a member of its shadow cabinet.

Asked on ABC radio on Thursday whether he intended to campaign against the Voice,Birmingham responded:“My perspective that I bring to this,I think,will be one of largely letting those who have the strongest views and the passionate opinions bring those forward.”

“I can certainly see some of the competing debates that occur on this issue. I respect those debates. Ultimately,I get ... a single vote in a referendum,the same as every other Australian,and that’s the way I’ll respect that process.”

Outspoken moderate Bridget Archer has said she intends to campaign for the Voice. The Tasmanian MP is the only sitting federal Liberal parliamentarian so far to publicly oppose the party’s position.

She was among a group of MPs,including Russell Broadbent,Andrew Bragg and Richard Colbeck,to speak against elements of the stance in Wednesday’s snap Liberal party room meeting,according to sources who asked not to be named so they could discuss the issue.

Another opposition frontbencher and Liberal moderate,Paul Fletcher,told ABC television on Thursday that,as a member of the shadow cabinet,he would be “making the case for Liberal Party policy”. But when asked how he would vote at the ballot box,he said:“I’ll be making my judgment based upon all of the considerations and information that becomes available.”

On Friday,Education Minister Jason Clare said Liberal opposition to the Voice made it more difficult for the referendum to succeed,“but the Australian people are bigger and better than this mean and negative Liberal Party and I have faith that they will meet this moment later this year”.

Cut through the noise of federal politics with news,views and expert analysis from Jacqueline Maley.Subscribers can sign up to our weekly Inside Politics newsletter here.