Meta on Tuesday announced that it was extending its teen accounts to its social network Facebook, after recently introducing restrictions on Instagram.

The accounts were brought in for 13- to 15-year-old users of the company's popular photo-sharing app last September as part of moves to shield vulnerable underage internet users from online harms.

Teens are immediately placed in such accounts, with those under 16 unable to change settings without parental permission.

In a statement, Meta said it was expanding the restrictions in the coming months to stop teens from going live or turning off protections for unwanted images in direct messages on their own.

"Teen Accounts on Facebook and Messenger will offer similar, automatic protections to limit inappropriate content and unwanted contact, as well as ways to ensure teens' time is well spent," it added.

The accounts will initially be available in the United States, Britain, Australia and Canada, then other countries at a later date.

At least 54 million teenagers currently have a teen account, which also limit overnight notifications and have reminders to leave the app after an hour.

Users can only be messaged by people they follow or are already connected to.

Adolescent use of social networks has prompted concern in recent years, notably about the amount of screentime and lack of moderation on some platforms.

In November last year, Australia's parliament voted in favor of a ban on under 16s from using social networks.

TikTok recently launched a function in the European Union allowing parents to limit the amount of time that teenagers spend on the app.