Two of the country’s biggest hospital operators say large insurance premium increases will not fix the private hospital crisis as they called for changes to the way the amount of funding insurers contribute to the healthcare system was calculated.

Healthscope said on Wednesday it was still in negotiations with major insurer Bupa for additional funding to prop up its hospital operations struggling with soaring costs. Medibank Private, NIB and HCF agreed earlier this year to give the group tens of millions of dollars in out-of-cycle funding payments.