A federal judge has blocked Donald Trump’s attempts to ban TikTok the latest legal defeat for his administration as it tries to wrest the popular app from its Chinese owners.

The Trump administration had tried to ban the short-form video app from smartphone app stores in the US and cut it off from vital technical services.

TikTok sued, arguing such actions would violate free speech and due process rights.

Judge Carl Nichols of the US District Court in Washington DC, said in a ruling that the Commerce Department “likely overstepped” its use of presidential emergency powers “and acted in an arbitrary and capricious manner by failing to consider obvious alternatives”.

He is the second federal judge to fully block the Trump administration’s economic sanctions against the app as the court cases proceed.

The administration has alleged that TikTok is a security threat because the Chinese government could spy on app users’ personal data. TikTok has denied being a security threat but said it is still trying to work with the administration to resolve its concerns.

Mr Trump in September gave his tentative blessing to a proposal by ByteDance, the Chinese company that owns TikTok, meant to resolve US national security concerns by having US companies Oracle and Walmart invest in TikTok.

Oracle would manage US user data under the arrangement, but a federal agency still has to review and finalize an arrangement.

A government deadline for ByteDance to complete the deal passed on Friday, and it is not clear what the status of the agreement is.

The Treasury Department said on Friday that the agency reviewing the deal “is engaging with ByteDance to complete the divestment and other steps necessary to resolve the national security risks arising from the transaction”.

The Trump administration’s aggressive tactics are part of its latest attempt to counter the influence of Beijing.

Since taking office in 2017, Mr Trump has waged a trade war with China, blocked mergers involving Chinese companies and stifled the business of Chinese firms like Huawei.

While president-elect Joe Biden has said TikTok is a concern, it is not clear if his administration will carry on Mr Trump’s attempts to secure a ban, or increase the involvement of US companies.