More than two decades of efforts by Microsoft to put down roots in China may soon bring a partial pay-off, if it succeeds in steering through the purchase of TikTok’s US business.

But as relations between the US and China continue to deteriorate, the software company’s long-term bet on the Chinese market is also facing its most uncertain period yet.

Microsoft’s involvement in the Chinese tech world, dating from its creation of a research centre in Beijing in the late 1990s, has left it with important personal connections. Zhang Yiming, the founder of ByteDance, the company that owns TikTok, worked at Microsoft, though only for a few months before he left to join a start-up.