An alleged conman charged with exploiting sick and dying kittens for cash has been filmed selling the underage felines in public parks across Melbourne despite already facing a string of serious fraud and animal cruelty-related charges.

Con Petropoulos, also known as Konstantinos Petropoulos, and his Russian-born wife, Liudmilla, are facing landmark criminal prosecution from the RSPCA and police over allegations they ran an illegal breeding racket from inside their suburban home then sold the kittens with fake documentation during 2017.

Secret parkland footage shows the pair offering kittens for sale in Richmond and Flemington as recently as last month.

The most recent exchange occurred just three days after the pair last fronted Geelong Magistrates Court relating to a November 2017 raid on their family home.