SYDNEY (Reuters) -Australia's internet watchdog on Wednesday widened its world-first teen social media ban to include Reddit ( RDDT ) and video live streaming platform Kick, and said more sites could be added if their main role was to enable online social interaction.

Australia will become the first country to fine social media firms up to A$49.5 million ($32 million) if they fail to take reasonable steps to block users aged under 16. The law will become effective from December 10.

* The eSafety Commissioner on Wednesday urged tech firms tocontinually assess whether they meet the definition of an'age-restricted social media platform' when they introduce newfeatures or their primary usage changes. * Discord, GitHub, LEGO Play, Roblox ( RBLX ), Steam and Steam Chat,Google Classroom, Messenger, Meta Platforms' ( META ) WhatsApp andYouTube Kids do not currently meet the criteria for anage-restricted social media platform, the regulator said. * Facebook, Instagram, Snapchat, Threads, TikTok, X, andAlphabet-owned YouTube have already been included in the list. * There will not be a static list of companies that areage-restricted because of the fast-changing nature oftechnology, eSafety said. * When new tech platforms emerge or existing ones changetheir purposes, eSafety said it may reassess those services. * "We will continue to take a whole of ecosystem approach,but we want to reinforce that just because a service isexcluded, it does not mean it is absolutely safe," eSafetyCommissioner Julie Inman Grant said in a statement. ($1 = 1.5389Australian dollars)

(Reporting by Renju Jose in Sydney; Editing by Lincoln Feast.)