Peter Dutton has rekindled his threat to forcibly break up insurance companies if they engage in anticompetitive conduct, in comments that point to division in his ranks and reflect his disdain for big business ahead of the election.

Despite his senior shadow ministers stressing over the past week that a Coalition government would only legislate for the forced divestment of supermarkets and hardware chains, the opposition leader said he would do the same to insurers if there was a concentration of power among “big insurers”.