Australia said on Wednesday it will add YouTube to sites covered by its world-first ban on social media for teenagers, reversing an earlier decision to exempt the Alphabet-owned video-sharing site and potentially setting up a legal challenge.

The Australian government has announced that YouTube will be included in new legislation that bans children under the age of 16 from using social media.

Officials in Australia had previously indicated they would exempt YouTube from the ban, which prohibits people under 16 from having social-media accounts.