The Morrison government is preparing to extend the $70 billion JobKeeper program, provide further relief on insolvent trading and bring forward tax cuts to allay concerns the Melbourne coronavirus outbreak could derail the nation's economic recovery.

Prime Minister Scott Morrison rallied support for Victoria, where another 134 cases were confirmed on Wednesday, thanking the efforts of other state and territory leaders for their co-operation in dealing with the surging second wave of COVID-19 that has forced border closures and a six-week lockdown of the entire city of Melbourne.