Australia will move to pass new laws banning children under 16 from social media, Prime Minister Anthony Albanese said Thursday, vowing to crack down on tech companies failing to protect young users.

"This one is for the mums and dads. Social media is doing real harm to kids and I'm calling time on it," he told reporters.

Albanese first mooted a social media age limit earlier this year, but it is the first time he has put a firm number on it.

Tech giants and social media platforms will bear the responsibility for ensuring users are old enough, Albanese said, rather than parents who were "worried sick about the safety of their kids online".

"The onus will not be on parents or young people. There will be no penalties for users."

Earlier proposals to introduce a social media age limit have enjoyed broad bipartisan support in Australia.

Albanese said the new laws would be presented to state and territory leaders this week, before being introduced to parliament in late November.