Broadcaster Alan Jones says the decision to sack Israel Folau over his latest social media attack on homosexuals is a "slippery slope" for free speech in Australia.

"Out there, people now are terrified of saying anything; they don’t know what they can say," Jones said on 2GB on Friday morning.

Broadcaster Alan Jones says the decision to sack Israel Folau was influenced by sponsors. Credit:AAP

Rugby Australia has vowed to terminate Folau's multimillion-dollar contract unless he can explain his social media post, in which he declared that hell awaits "drunks, homosexuals, adulterers, liars, fornicators, thieves, atheists and idolaters".

Jones said that Rugby Australia, in making its decision, was only worried about the potential loss of sponsorship money.