Hearing France had won the $50 billion contract to help build the fleet of 12 in Adelaide, South Coast Labour Council secretary Arthur Rorris said the announcement would “open up the flood gates” to use Australian steel in government projects across the country.

He particularly welcomed Mr Turnbull’s comments which said: “Over decades to come, the submarine project alone will see Australian workers building Australian submarines with Australian steel here, where we stand today, for decades into the future.” 

However, by Tuesday afternoon a media release saying the government would “maximise Australian industry involvement in the program and … work closely with [French company] DCNS to identify opportunities for local businesses to integrate into the supply chain” had cast doubt over how much involvement local steelmakers would have in the Defence project.

“They say a day can be a long time in politics, but I didn’t think victory could be so short-lived,” Mr Rorris said.

“It now appears that the federal government is reworking the script from ‘using Australian steel’ to ‘assessing our needs’. Let’s hope there’s more Australian steel in this project than the staples holding the contract together.”

Campaigner Ian Waters, of K&R Fabrications, had also assumed the PM’s statement would mean a big windfall for BlueScope’s plate mill, which he said was the only Australian producer capable of making the material’s for a submarine hull.

Likewise, Throsby MP Stephen Jones said both BlueScope and Unanderra-based Bisalloy were well placed to produce the products needed for the submarines. 

However, he noted there had been no guarantee from Mr Turnbull about how much Australian steel would be used.

“Between them BlueScope and Bisalloy can produce the steel that is needed for these sub contracts,” Mr Jones said.

“There is absolutely no doubt about that, that they can produce what is needed. The only question is whether the government wants that to happen.

“It would be a disgrace if they were excluded given that Bisalloy provides hardened steel defence industries in other countries. It would be ludicrous if they didn’t do it for an Australian project.”

Mr Turnbull said in Adelaide that “the bulk of the work will be done here” though there would be a supply chain that stretched across the country and some components such as the US-made combat system will be sourced overseas.

However, he reportedly dodged questions about the exact percentage of the build that will take place in Australia, saying those negotiations have not been settled.

He said the decades-long submarine program would create about 2800 direct jobs and help Australia transition to a 21st century economy.