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.

Suri, 17, said young people needed to be "responsible for themselves" and be disciplined in "not going to find content they weren't ready for" but she admitted social media could be "devastating", leaving people "helpless".