Victoria will send police into 10 postcodes, impose lockdown restrictions on all businesses; and divert planes from Melbourne to fight a surging coronavirus outbreak the Premier has blamed on flagrant breaches of infection controls by hotel quarantine staff.

Premier Daniel Andrews said he was taking "extraordinary steps" to send in police to lock down 36 suburbs in 10 hotspots, largely in Melbourne's working class north and north west, for four weeks from midnight on Wednesday to get the "wildly infectious" outbreak under control.