The UK Government has now changed its stance, and announced an immediate ban of the Chinese-owned app on all Government employee phones after initially resisting calls to do so.
TikTok is now in line with the EU, which enacted a ban of TikTok on Government devices last month, while the majority of US states have now also banned the app from Government-owned phones.
As reported by The Guardian:

The UK decision follows a review of TikTok by government cybersecurity experts that began in November, and will cover ministers' and civil servants' work phones, but not their personal phones. [Cabinet Office Minister Oliver Dowden says] this is a 'proportionate move based on a specific risk with government devices'."

Amid rising global tensions, these concerns regarding the Chinese-owned app and the possibilities of the app being a spying tool have become much more pressing for many cybersecurity experts because TikTok could track citizens' movement and monitor what users were doing.
And those reports do have precedence.

Late last year, it was reported that representatives of ByteDance, which owns TikTok, tracked the movements of US journalists for the purpose of identifying people in the company who may have been leaking information to the media.

This is the core issue around the misuse of TikTok data, and in this light, the increasing bans of the app on government-owned devices make sense, as that could be used as a vector to track people's movements, and monitor who they're meeting with.

There is some risk to the government employees who are supposed to carry this sensitive information; therefore, it does make sense that officials would be raising alarms and acting in this case.

The question then is whether this should be extended to everyone using TikTok, which is at the heart of a considered ban in the US. This week's latest is that the White House is reportedly pressuring TikTok into selling off from its owners in China if it would like to continue its existence in the region.

That's nearly exactly what former President Donald Trump proposed back in 2020, which nearly saw TikTok sold to a consortium led by Oracle, before the incoming Biden Administration abandoned those plans.

It looks like TikTok is forced to reconsider similar options these days – though it is notable that the sale of TikTok as such a Chinese asset would also need an approval from the Chinese Government, which has time and again expressed its disapproval of the various bans that have been imposed on the app.

TikTok, too, continues its voice against these actions. On the UK ban, a TikTok spokesperson had said:
We believe these bans have been based on fundamental misconceptions and driven by wider geopolitics, in which TikTok, and our millions of users in the UK, play no part. We remain committed to working with the government to address any concerns.

Which, of course is the response you might expect, but it's interesting to see TikTok make reference to geopolitical tensions, and invoke nationalistic fears, as a means to oppose the expanding bans.

Look, right now, there doesn’t seem to be a clear case for a full TikTok ban, as there wasn’t when the US initially proposed a ban under Trump in 2020. But that doesn’t mean that it won’t happen - and really, it feels like we’re very, very close to the edge on this, amid accusations of spying and international interference on several fronts.

The proposal to force TikTok into a sell-off, if the US Government does press this, could potentially secure billions in revenue for the company, and that seems like too much to leave behind for TikTok, if it comes down to it.

But again, the Chinese Government may look to make a statement instead, and resist western bullying.