Wind Down aims to make under-16s move away from the app before they get some sleep.

The social media platform has programmed the tool so that it will automatically turn on if a user is on the short-form video hosting app after 10pm.

As well as a full-screen takeover of the For You feed, it will play calm music to help the user to relax.

If a teen decides to spend more time on TikTok after the first reminder, it will display a second, harder to dismiss, full-screen prompt.

Push notifications will not be sent to teens at night.

The ByteDance-owned platform has also added a new parental control feature called Time Away to the app, which will allow adults to ban their teenage children from using TikTok during select times during the day.

TikTok said in a statement: "We designed these features to reflect best practices in behavioural change theory by providing positive nudges that can help teens develop balanced long-term habits.

"In countries where this has already been piloted, the vast majority of teens decide to keep this reminder on.

"In the coming weeks, we'll also test adding meditation exercises to the wind down reminder, as research shows that mindful meditation can improve sleep quality."