Public support for the Aukus nuclear submarine acquisition and the Indigenous voice to parliament have both declined, according to the latest Guardian Essential poll.
The poll of 1,124 voters, released on Tuesday, suggests Australians are at odds with the Aukus deal, with just one in five voters labelling China a “threat to be confronted” and only one quarter happy to pay the price tag of up to $368bn to acquire nuclear submarines.
It also finds that support for the voice is down 5%, although with 59% in favour it still commands majority support.
Last week Anthony Albanese, alongside the US president, Joe Biden, and UK prime minister, Rishi Sunak, announced the acquisition of up to eight nuclear submarines, including US Virginia class submarines in the 2030s and the new SSN Aukus class in the 2040s.
In the poll, 40% of respondents said the submarine partnership would make Australia more secure, down four points since November. Those who said the nation would be less secure rose four points to 21%, while 39% said it would not affect security.
The plan will cost between $268bn and $368bn, or 0.15% of GDP a year on average over 50 years.
Respondents were split on the cost, with 26% saying Australia needed nuclear submarines and “it’s worth paying that amount to get them”, while 27% said they were necessary but “not worth” the price tag, 28% said Australia does not need them and 19% were unsure.
Given the bipartisan support for Aukus from Labor and the Coalition, opposition to the plan was led by the former prime minister Paul Keating, the Greens and former Labor parliamentarians Doug Cameron and Peter Garrett.
The defence minister, Richard Marles, on Sunday said China’s rapid military buildup “shapes the strategic landscape in which we live”, telling the ABC’s Insiders that the Aukus submarines would back up Australia’s interest in protecting trade and freedom of navigation and flight in the South China Sea.
Two-thirds (67%) of respondents in the poll said Australia’s relationship with China was a “complex relationship to be managed”, up seven points since February.
The proportion who described China as a “threat to be confronted” fell by six points to 20%, while a steady 13% said the relationship was a “positive opportunity to be realised”.
From August to February, support for the Indigenous voice to parliament was steady in the range of 63% to 65%. But in March support slumped five points to 59%, a movement outside the poll’s margin of error. Support among men was down two points to 56% and among women down eight points to 63%.
A decline in support was recorded in all age groups, with 79% of those aged 18-24 in favour of the voice (down seven points), 64% of those aged 35-54 (down five) and 40% of those 55 and over (down four).
The Coalition has warned that the Albanese government has not released enough detail about the voice, but support among Coalition voters actually increased by two points to 43%.
In the first poll since Senator Lidia Thorpe quit the Greens to pursue black sovereignty as an independent, a big fall in support for the voice was recorded among Greens voters, down 12 points to 77%.
While there is a majority of support for the voice in New South Wales, Victoria and South Australia, the results are finely balanced in Queensland (49% in favour and 51% opposed) and Western Australia (55% in support and 45% opposed).
To be successful, the referendum requires a majority in the nationwide vote as well as a majority of states, meaning negative results in three states could sink the proposed change.