Media regulator Coimisiún na Meán has found that TikTok, X and Instagram are "exposed to terrorist content".
The organisation has issued the decision following the notification of removal orders to these platforms from EU authorities.
The companies must now take specific measures to prevent their services from being used for the dissemination of terrorist content and to report on the measures they have taken.
Under EU law, terrorist content includes material that incites the commission of terrorist offences, as well as content that provides instruction on the making or use of explosives, firearms, or other weapons.
Under the Terrorist Content Online Regulation, hosting service providers which receive two or more final removal orders from EU authorities within the last 12 months may be determined as being exposed to terrorist content.
Among the measures a hosting service provider exposed to terrorist content is required to take is the inclusion in its terms and conditions of provisions to address the misuse of its service for the dissemination to the public of terrorist content.
"Infringement by hosting service providers of the Terrorist Content Online Regulation can lead to the imposition of administrative fines, including financial penalties of up to four percent of global turnover," Coimisiún na Meán said.
