Australia’s Catholic bishops are calling for a crackdown on media platforms like Facebook, Google and Twitter.

The bishops say platforms should be fined for sharing fake news and offensive content to ensure basic standards are not lost in a profit-maximising scheme.

The Australian Catholic Bishops Conference says governments "have a responsibility to support robust and independent journalism, particularly through the public broadcaster."

They say they also want action to address the viral spread of half-truths, lies and slander.