The European Commission on Friday accused TikTok of purposefully designing its app to be “addictive,” calling out features such as infinite scroll, autoplay, and push notifications, as well as its recommendation engine.

In preliminary findings from an investigation that sought to determine TikTok’s compliance with the European Union’s far-reaching Digital Services Act, the Commission said the short video platform did not “adequately assess” how its design decisions could harm the well-being of its users, particularly minors and vulnerable adults.

The EU’s executive arm said the company disregarded “important indicators of compulsive use of the app” like the time users spend at night and how often users open it.

“By constantly ‘rewarding’ users with new content, certain design features of TikTok fuel the urge to keep scrolling and shift the brain of users into ‘autopilot mode.’ Scientific research shows that this may lead to compulsive behaviour and reduce users’ self-control,” the Commission wrote in a statement.

The Commission said TikTok must change the “basic design” of its user interface by disabling features like infinite scroll, implementing screen time breaks, and changing its recommendation system.

TikTok denied the allegations.

“The Commission’s preliminary findings present a categorically false and entirely meritless depiction of our platform, and we will take whatever steps are necessary to challenge these findings through every means available to us,” a TikTok spokesperson said in an emailed statement.

TikTok does offer screen-time management tools and parental controls, but the European Commission said those tools don’t do enough to reduce the risks of its addictive design. “The time management tools do not seem to be effective in enabling users to reduce and control their use of TikTok because they are easy to dismiss and introduce limited friction. Similarly, parental controls may not be effective because they require additional time and skills from parents to introduce the controls,” the Commission wrote.

The allegations against TikTok come as social media platforms deal with heightened scrutiny around the world, with some governments pushing to ban young users from accessing social media altogether. In November, Australia mandated social media sites to deactivate accounts belonging to users under 16, and the U.K. and Spain are reportedly looking into similar measures. France, Denmark, Italy, and Norway have worked on similar age-restriction measures for social media platforms, and in the United States, 24 states have so far enacted age-verification laws.

TikTok recently settled a major social media addiction lawsuit in the U.S., and it now has time to reply to the European Commission’s preliminary findings. Confirmed breaches of the DSA can face a range of major sanctions, including fines of up to 6% of global annual turnover.

This story was updated to add TikTok’s response.