In March, Sen. Josh Hawley, a Republican from Missouri, proposed a bill to ban federal employees from using TikTok on their government-issued phones as concerns increase about Chinese tech firms sharing user data with Beijing. Several U.S. agencies, including the State Department and the Department of Homeland Security, have already barred employees from using the app.

--Stu Woo contributed to this article.

Write to Rajesh Roy at rajesh.roy@wsj.com and Shan Li at shan.li@wsj.com