Cat owners who live near areas containing threatened species could be banned from allowing their pets outdoors as the federal government sets its sights on the potential killing machines.

Australia's first threatened species commissioner, Gregory Andrews, said all cat owners should keep their pets contained 24 hours a day, saying it makes them happier and healthier, and saves native mammals.

The government is seeking to control feral cats. Credit:Kate Leith

But a veterinarian said the measure, already in place in some jurisdictions, could cause health and behavioural problems and should be implemented with caution.

The government's feral cat plan, released this month, has drawn ire from cat lovers the world over - including French film legend Brigitte Bardot - as it sets out to cull 2 million feral cats.