Electrical Trades Union branch organiser Damian King said for 70 years workers at the Mulwala plant had been classified as manufacturing workers and the change would result in reduced conditions.

He said the 570 workers represented by three unions, the ETU, the Australian Workers Union and the Australian Manufacturers Workers Union, unanimously rejected the EBA.

Mr King said if Thales and the government succeeded in classing staff as construction workers they would be exposed to 'a major reduction in entitlements', claiming minimum wages for production workers could fall from $27 per hour to $20.

ETU Victorian secretary Troy Gray accused the government and the Australian Building and Construction Commission of overreach.

"These are not building workers, they make bullets, bombs and shells," he said.

"The Morrison Government is seeking flimsy excuses to redefine their work and drive down wages."

However Thales Australia and the federal government rejected the unions claims.

IN OTHER NEWS:

A Thales spokesman said no final EBA proposal had been put to the sites' 680 staff.

He said there had never been any proposal to reduce wages and the agreement would provide a wage increase.

"Legal compliance is essential for Thales to continue to win Commonwealth contracts and to provide job security to our workforce," he said.

A spokesman for the Department of Jobs said the government had no involvement in workplace agreements.

"Bargaining is entirely a matter for the relevant bargaining parties," he said.

"This is nothing more than a union, egged on by the Labor Party, deciding to play politics with workers' livelihoods.

"Commonwealth funded building work must be compliant with the Building Code, which ensures best practice regarding workplace relations, worker safety and zero tolerance for drugs and alcohol."

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