Construction workers plan protests over takeover move

Workers will down tools in solidarity with the CFMEU as it moves to challenge external administration in the courts.

Rallies will take place in capital cities on Tuesday after the union's construction arm and all associated branches were taken over following allegations of criminal links and corruption.

Angry rank-and-file union members have taken to social media groups condemning the government's action against the CFMEU.

The Maritime Union is backing the protest, calling the administration process an "attack on trade unionists' rights and democracy".

The Electrical Trades Union has also called for members to support the protests.

While people have a democratic right to peaceful protest "the taking of unprotected industrial action is not lawful", a spokesperson for the CFMEU administrator said.

"The CFMEU is no longer involved in organising any protest tomorrow," they said.

The union has also flagged a legal fight to the process.

"What else is new?" Prime Minister Anthony Albanese said on ABC Radio on Monday, when asked about a court challenge.

"That's business as usual from the CFMEU."

Victorian Public Transport Minister Gabrielle Williams said she respected the people's right to protest, despite the looming rallies being unprotected.

She wouldn't be drawn on whether the state government would seek penalties if workers illegally walked off its major project sites.

"We'll be keeping an eye on these actions and working really closely with our project partners to ensure that we can overcome those challenges and ultimately keep our sites and Victorians safe," Ms Williams told reporters in Melbourne.

The unprotected stoppages would lead to more costs and delays to already crisis-riddled major projects, Victorian Opposition Leader John Pesutto said.

Former union boss John Setka claimed a deal had been struck with the federal government that he would resign to ensure the construction union was left alone.

He has accused Labor of betrayal.

Opposition workplace relations spokeswoman Michaelia Cash said any alleged deal needed to be investigated and was "highly alarming".

"Mr Albanese has serious questions to answer," she said.

The prime minister's office referred to Workplace Relations Minister Murray Watt's comments, who branded allegations of a deal "absolutely fanciful" and a desperate attempt from Mr Setka to distract from the problems within the union.

Mr Albanese also dismissed a claim by Mr Setka that he was "trembling" in a lift with him.

"Nonsense, I didn't watch the interview and I don't know why they gave him air time," he said of the Seven Network's report.

CFMEU national secretary Zach Smith has chastised the government for going over the top of the union to appoint an external administrator, saying it stripped members of their right to due process.

The union had taken the allegations seriously and commissioned a forensic audit, put in place a new code of conduct for delegates and stood down people accused of wrongdoing.

"It is a sad indictment on the federal government and all sides of politics that have succumbed to anti-CFMEU rhetoric spouted by big business and amplified by conservative media outlets," he said in a defiant video message to members.

The union is in administration for a minimum of three years and up to five, and officials who frustrate or obstruct the process face hefty fines and jail time.