Former President Donald Trump has joined TikTok and amassed over 650,000 followers within the first 24 hours of launching his account, CNN reports. The 77-year-old posted his first video on the platform after attending an Ultimate Fighting Championship (UFC) event in Newark, New Jersey, featuring UFC CEO Dana White. In the video, Trump said it was an “honor” to be on the app, followed by clips of cheering UFC fans.

Trump’s presence on TikTok represents a significant shift from his stance during his presidency when he sought to ban the Chinese-owned app due to national security concerns. Despite this, his super PAC, MAGA Inc., joined the platform in May, with CEO Taylor Budowich stating their intention to bring Trump’s “America First agenda” to every corner of the internet.

The former president’s about-face on TikTok comes as the platform continues to grow in popularity, particularly among younger users. With 170 million users in the United States, TikTok is one of the fastest-growing social media networks, though it still trails behind Instagram and Facebook in total user count.

Both the Trump and Biden campaigns have established a presence on TikTok, even as the Biden administration supports a nationwide ban on the app. TikTok has filed a legal challenge to the law signed by President Biden in April that would ban the app unless it finds a new owner, with oral arguments scheduled for September.

According to CNN, Trump’s launch video on TikTok had been viewed more than 6 million times on Sunday morning, indicating significant interest in his presence on the platform.