TikTok is urging a federal court to block US President Donald Trump from banning the video app, arguing the move is motivated by election politics rather than legitimate national security concerns.

The Chinese-owned app -- which is wildly popular in the US -- has come under fire as tensions escalate between Beijing and Washington, with Trump threatening a ban if it is not sold to an American company.

Attorneys are set to argue the case on Thursday before a judge who will decide whether to put Trump's order on hold until a lawsuit over the ban is resolved.

Citing "confusing and contradictory statements about TikTok" by the president and other agencies, the motion for a preliminary injunction argues a ban is not motivated by "genuine national security concern, but rather by political considerations relating to the upcoming general election." 

TikTok, which became a global phenomenon with its brand of short, addictive phone videos, has some 100 million US users.

A deal to restructure ownership of the app was thrown into doubt Monday when Trump vowed to block a deal that allows its Chinese parent firm ByteDance to retain any control.

The comments cast doubt over an agreement that had appeared to cut a way through the threatened ban.

The deal would make Silicon Valley giant Oracle the data partner for TikTok, with retail giant Walmart also taking a minority stake in a new entity to be called TikTok Global.

As competing statements deepened the mystery over the app's future, ByteDance earlier said TikTok Global plans to launch a "small round of pre-IPO financing" after which it would become an 80 percent-owned subsidiary of ByteDance.

But Trump told Fox News om Monday that TikTok's Chinese parent firm "will have nothing to do with it."

Oracle and Walmart "are going to own the controlling interest," he added. "Everything is going to be moved into a cloud done by Oracle... and it's going to be controlled -- totally controlled by Oracle."

ByteDance said Thursday that it had applied for an export license with the commerce ministry, although it did not link the move to TikTok or any potential sale.

China's commerce ministry published new rules in August that added "civilian use" to a list of technologies that are restricted for export and require permission, which could complicate any sale.

Winning a temporary injunction typically involves convincing a judge that not intervening would allow irreparable harm to be done to a party likely to win the case.

TikTok would suffer "devastating harm" from which it could not recover if Trump's ban is found to be unlawful, the motion argued.

As US relations with China grew more contentious, Trump began targeting TikTok, the filing read.

The motion also speculated that TikTok had irked the president because of reports the app was used by his critics to snatch up tickets to a Trump rally in Tulsa to which they had no intention of going -- an event which belly flopped with significantly fewer people in attendance.