Washington DC - Video app TikTok is mobilizing its US users with a warning that the app could be banned in the country.

"Congress is planning a total ban of TikTok," said a notification from the popular video-sharing platform on Thursday. There was a button on the display to call the members of the US Congress from the users' respective constituencies.

The tech website The Information reported that one representative's office was so inundated with calls that staff had no choice but to switch off the phones.

TikTok's warning was a reference to a bill that is currently being drafted in the US House of Representatives.

The document, prepared jointly by Democrats and Republicans, would give TikTok owner Bytedance just under six months to relinquish control of the popular app.

Otherwise, TikTok could be banned from app stores in the US. The service claims to have 170 million users in the US.

Some politicians have expressed concerns that the app could be misused by Chinese authorities to collect information about users. Governments of several countries, including the United States, have banned the use of TikTok on government phones.

TikTok rejects concerns and emphasizes that it does not see itself as a subsidiary of a Chinese company. Bytedance is 60% owned by Western investors. The company is based in the Cayman Islands in the Caribbean.

Critics counter that with a share of 20%, the Chinese founders have control thanks to higher voting rights and that Bytedance has a large headquarters in Beijing.

During his term as president, Donald Trump tried to enforce the sale of TikTok's US business to American investors by threatening to ban it. The plan failed because US courts ruled that a TikTok ban violated the freedom of speech enshrined in the US constitution.