Scott Morrison’s post-budget sell has been derailed by a vicious personal attack from Liberal senator Concetta Fierravanti-Wells, who labelled the Prime Minister an autocrat who lacks a moral compass and is unfit to govern.

Senator Fierravanti-Wells, a right factional warrior who lost her preselection at the weekend, accused Mr Morrison and Immigration Minister Alex Hawke of ruining the NSW Liberal Party with a federal executive intervention over unresolved lower house pre-selections.