The case was brought by three TikTok creators, who argued that President DonaldTrump's executive order directing a complete US ban on the Chinese-owned short-form video app infringed their First Amendment rights to free expression.

The White House has claimed TikTok, because of its ties to China, represents a national security threat.

In the ruling on Friday granting a preliminary injunction to halt ban, District Judge Wendy Beetlestone of the US District Court for the Eastern District of Pennsylvania wrote that the plaintiffs "have demonstrated a clear likelihood of irreparable harm".

She also found that the US government's "own descriptions of the national security threat posed by the TikTok app are phrased in the hypothetical" and therefore she could not find that "the risk presented by the government outweighs the public interest in enjoining" the ban.

The decision comes after a separate September 28 ruling by a federal judge blocking the White House's ban on TikTok downloads in the US - just hours before that was to go into effect.

In that case, which was brought by TikTok, the judge ruled that the Trump administration "likely exceeded the lawful bounds" of the powers afforded to the president under the the International Emergency Economic Powers Act.

The Department of Justice has appealed that decision.

TikTok is used by over 100 million users in the US alone and 50 million use it daily, according to the lawsuit.

The ban would eliminate the creators' ability to earn money through TikTok, the app's creators argued

In a statement about Friday's ruling, TikTok's interim global head Vanessa Pappas said, "We are deeply moved by the outpouring of support from our creators, who have worked to protect their rights to expression, their careers and to help small businesses, particularly during the pandemic. We stand behind our community as they share their voices, and we are committed to continuing to provide a home for them to do so."

Australian Associated Press