The White House made its official debut on TikTok, marking a significant shift in the administration’s approach to the Chinese-owned social media platform that was slated for a ban just days before President Trump took office.

The administration’s inaugural post on Tuesday featured a 27-second video with the caption, “America we are BACK! What’s up TikTok?” By Wednesday morning, more than 100,000 people had followed the account.

The launch comes as Mr. Trump continues to allow TikTok to operate in the United States despite federal legislation that required the platform’s sale or prohibition on national security grounds. The law was originally set to take effect on January 19, a day before Mr. Trump’s inauguration, and survived a challenge in the U.S. Supreme Court.

“The Trump administration is committed to communicating the historic successes President Trump has delivered to the American people with as many audiences and platforms as possible,” the White House press secretary, Karoline Leavitt, said as the account launched.

Mr. Trump’s relationship with TikTok has undergone a dramatic transformation. The president initially championed efforts to ban the platform in 2020, citing national security concerns over its Chinese ownership. However, he reversed course after joining the app during his 2024 campaign, where he accumulated nearly 15 million followers on his personal account.

The president now credits TikTok with helping him connect with younger voters in his victory over his Democratic opponent, Vice President Kamala Harris, in the November election. Mr. Trump’s personal TikTok account, which has more than 15 million followers, last posted on November 5, 2024 — Election Day.

TikTok’s popularity in the United States is undeniable, with 170 million American users on the platform. The app’s parent company, ByteDance, indicated in April that it had been in discussions with the American government regarding a resolution, noting that any agreement “will be subject to approval under Chinese law.”

In June, Mr. Trump extended the deadline for TikTok to find a non-Chinese buyer by an additional 90 days — the third such extension. That deadline is set to expire in mid-September.

The issue of TikTok’s future had gained bipartisan support in Congress, which voted overwhelmingly to ban the app last year. The legislation faced legal challenges but was ultimately upheld by the Supreme Court.

Mr. Trump’s evolving stance on TikTok became apparent during his campaign when he hosted TikTok’s CEO, Shou Zi Chew, at his Mar-a-Lago estate in Florida. Mr. Chew also attended Mr. Trump’s inauguration ceremony.

The president maintains a significant social media presence across multiple platforms. His official X account boasts more than 108 million followers, though he frequently uses Truth Social, his own platform, where he has 11 million followers. The official White House accounts on X and Instagram have 2.4 million and 9.3 million followers, respectively.