CFMEU members are expected to walk off major construction sites across the country on Tuesday after sacked leaders of the NSW branch held a secret meeting and called for the national action, despite the union being forced into administration last week.

The meeting of delegates on Monday could expose the former officials, including ex-CFMEU NSW secretary Darren Greenfield, to fines of up to $187,000 or criminal penalties of up to $939,000 or two years’ jail if they are found to have undermined the union’s administration.