TikTok has filed a lawsuit against the US state of Montana for banning residents from accessing its social media platform.
Monday's lawsuit comes after last week Montana became the first US state to pass a sweeping ban on the Chinese-owned video-sharing platform.
The TikTok lawsuit argues that the ban violates the constitutional First Amendment right to free speech.
TikTok has come under scrutiny from authorities around the world over concerns that data could be passed to the Chinese government.
The company's complaint states that the ban was "unconstitutionally shutting down the forum for speech for all speakers on the app".
The ban is due to take effect in January 2024. TikTok says it has 150m American users.
Although the app's user base has expanded in recent years, it is still most popular with teenagers and users in their 20s.
However, there are concerns across the US political spectrum that TikTok could be a national security risk.
The social media platform is owned by ByteDance - a Chinese company. However, ByteDance has repeatedly denied it is controlled by the Chinese government.
It says the ban is based on the "unfounded speculation" that China's government could access TikTok data. (With inputs from BBC)
