The video-sharing platform's Beijing-based parent company, ByteDance, had been in negations with the Department for International Trade and Downing Street officials to create new jobs at the firm in the UK.
However, as reported by The Guardian, it's now believed around 3,000 jobs could be lost after executives claimed "wider geopolitical context" is to blame for halting the plans for a UK HQ in the British capital after the country banned Huawei from being part of its 5G mobile network.
It's also claimed that TikTok is now looking at Dublin in Ireland instead of London to build its base outside of China - where they already have some staff.
The report comes after the White House revealed they are expected to make a formal decision on whether or not to ban TikTok in "weeks, not months".
Following Secretary of State Mike Pompeo stating that they are "certainly looking at" banning the app, President Donald Trump's chief of staff, Mark Meadows, suggested last week, that they are working swiftly to look at apps such as the video platform and We Chat, which they believe pose major security risks.
Meadows told reporters this week: "There are a number of administration officials who are looking at the national security risk as it relates to TikTok, WeChat and other apps that have the potential for national security exposure, specifically as it relates to the gathering of information on American citizens by a foreign adversary.
"I dont think there's any self-imposed deadline for action, but I think we are looking at weeks, not months."
TikTok has profusely denied the app is a threat, and has also distanced himself from Douyin, the Chinese version of the app.
The firm - which has a new CEO in ex-Disney chairman Kevin Meyer - also no longer operates in Hong Kong, after the national security law was placed in the power of the Chinese government.
Responding to Pompeo, TikTok insisted: "TikTok is led by an American CEO, with hundreds of employees and key leaders across safety, security, product, and public policy here in the US.
"We have no higher priority than promoting a safe and secure app experience for our users. We have never provided user data to the Chinese government, nor would we do so if asked."