The Abbott government will target union access to the workplace and the negotiation process on so-called greenfield sites as it builds on its new-found momentum on industrial relations.

Following its calls for a rethink on penalty rates and what it calls cushy enterprise agreements, as well as its renewed push for reinstate the building industry watchdog, the coalition has flagged changes to the Fair Work Act ahead of parliament resuming next week.

The Fair Work Amendment Bill will overturn Labor’s changes of last year, which controversially allow unions to hold lunchroom meetings.

The legislation will also tackle so called “greenfield agreements” so unions cannot veto commencement of new projects, like major mining ventures, to extract better wages and conditions.

Employment Minister Eric Abetz has said that if negotiations over greenfield sites are not completed within three months, then businesses would be able to take agreements to the Fair Work Commission.

The government has listed the bill as a priority for the autumn session of parliament.

Laws to reinstated the Australian Building and Construction Commission are currently stuck in the Senate, with Labor and the Greens refusing to back them.