(Bloomberg) -- An Australian lawmaker from the ruling center-left Labor Party broke ranks with colleagues to publicly raise concerns over his government’s plan to acquire nuclear submarines under the Aukus agreement, as polls show voters worried about the deal’s huge cost.

Labor politician Josh Wilson said Tuesday in a speech to Parliament that there were “considerable risks and uncertainty” in the Aukus submarine deal. Under the plan, Australia would buy US-made nuclear-powered vessels in the early 2030s and then manufacture its own based on a UK design in the early 2040s.

Wilson, 50, said submarine construction “takes longer and costs more than you anticipate,” and flagged his fears about disposal and storage of the nuclear waste generated. 

“We haven’t yet managed a storage solution for low-level waste after 40 years and more than A$50 million,” he said. “Now we are taking on the challenge of safely disposing high-level waste, a problem no country has solved.”

It’s unusual in Australia for lawmakers from the ruling party to publicly speak out against their own government’s policy, especially in matters of national security. Wilson was elected in 2016 to the seat of Fremantle in Western Australia. The state is expected to be one of the major beneficiaries of the Aukus deal due to the presence of Australia’s Fleet Base West there.

His speech came as Prime Minister Anthony Albanese was questioned three times during the Labor party’s weekly meeting on Tuesday over the planned purchases. This included queries on the potential A$368 billion ($246 billion) price tag and whether workers would be taken from other parts of the economy to help build the vessels.

Albanese told lawmakers that the cost of Aukus up to 2027 had been offset by spending cuts, and more detail on defense expenditure would be available in a major review that will be released next month.

New polling released by Essential Media on Tuesday found diminishing support for the Aukus partnership with the US and the UK. Some 60% of respondents said acquiring nuclear submarines would either leave Australia’s security unaffected or make the country less safe.

While 26% of those surveyed by Essential said it was worth paying a large amount to acquire nuclear submarines, 55% said either the cost was too high or there was no need for the vessels in the first place.

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