US tech giant Meta Platforms has unveiled a set of enhanced privacy controls to protect teenage users on Instagram.

The company announced a new "Teen Accounts" designation on Tuesday. The feature automatically places built-in protections on accounts belonging to users under the age of 18.

Meta says these users will now only be able to receive messages from accounts they follow or are already connected to.

They will also get notifications telling them to close the app after 60 minutes each day. And an anti-bullying feature filters out offensive words and phrases.

Users under 16 will not be able to opt out of these restrictions without permission from their parents.

Meta says new accounts created by children under 18 would be automatically placed into the settings starting on Tuesday.

It plans to gradually phase in the controls for teenagers who already had accounts--within 60 days for those in the US, Canada and the UK, and starting in January for other parts of the world.

The changes come as social media firms face increasing pressure to better protect children from bullying, sexual extortion and other dangers on their platforms.