Labor left 50 major gas and energy projects in limbo after changing environment laws to include a water trigger for extra assessments.
Environment Minister Greg Hunt said it was a "major surprise" to discover the projects had been left hanging.
"They brought in a water trigger and then made no decisions," he told Sky News on Sunday.
"So 50 major gas and energy projects are in complete limbo."
He uncovered the projects during departmental briefings after being sworn in as minister on Wednesday.
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Mr Hunt is yet to see detailed briefings on the 50 projects but said he would start this week working through making decisions on whether to refer them for further environmental assessment.
"The previous ministers of Mr (Tony) Burke and Mr (Mark) Butler weren't asked to say yes or no to the projects, all they were asked to do was to make a procedural decision as to whether or not these projects needed to be considered," Mr Hunt said.
"How do you as a government ... change the law and then leave 50 major projects in limbo without the courage or the organisation or the wit to make one single decision?"
