Construction union officials may soon be removed from embattled branches of the CFMEU, through federal parliament or the courts.
Workplace Relations Minister Murray Watt will introduce laws when parliament returns next week to give him the power to appoint an administrator to the CFMEU's construction and general division for three years.
The threat followed calls for the union to submit to a Fair Work Commission application to appoint an external administrator to the division and some state branches.
Senator Watt said the union's national secretary Zach Smith told him consent "only remains a possibility", he said.
"The construction division of the CFMEU has clearly failed to operate effectively or in the best interest of its members - urgent action is required and it's required now," Senator Watt told reporters in Brisbane on Friday.
The minister gave construction union officials an ultimatum to comply with investigations into criminal links or face serious penalties.
The union criticised the government for jumping the gun on the legislation as it works with the Fair Work Commission's general manager on the administration application
The government's actions had "undermined the legal process and stripped us of our rights to a fair process," Mr Smith said.
"This is simply about exercising due diligence, which is our obligation as officers of a member-run organisation.
"We cannot 'walk in blind' to a process of administration without understanding the detail."
Mr Smith chastised Labor's "blue-collar paternalism" in pushing for external administrators after the union-appointed former anti-corruption tsar Geoffrey Watson to independently investigate criminal claims.
People had been removed and stood down from the union pending investigations and the minister hadn't replied to a union request for advice on further action, he said.
Senator Watt and senior ministers have said they didn't have confidence in the CFMEU being able to clean its own house.
Opposition workplace relations spokeswoman Michaelia Cash called for the union to be deregistered.
Labor has rejected deregistration, arguing it would put the union outside regulation.
The coalition's final position would be decided after the details of the bill had been worked through party processes, Senator Cash said.
The proposed law includes obligations for officers, employees and professional advisers to co-operate with any administrator, including providing all required information and documents.
Significant penalties will be imposed for those who do not comply, or try to frustrate or undermine the administration process.
It only applies to the CFMEU's construction and general division and no other divisions or unions.
Whistleblower protections will safeguard people coming forward with reports of wrongdoing.
The government is confident it can pass the legislation with minimal fuss after constructive talks with the Greens and some crossbench members.
Independent senator Tammy Tyrrell said she supported appointing an administrator in principle but was waiting for the bill's details.
"No organisation should expect serious, numerous allegations of criminal misconduct against its leadership to simply blow over," she told AAP.
The opposition is also pushing for a parliamentary committee to examine the CFMEU's involvement on construction sites and associated cost blowouts, and companies being locked out of building sites.
Senator Watt branded it a "political stunt" and ruled out Labor's support.
