There's no hard evidence that China is using its tech firms for espionage, says Jake Moore, global security advisor to ESET, an internet security firm.
However, he says: "There's a fear that firms like Huawei and TikTok have become so big that they could be hacking huge amounts of data and damaging national security.
"Governments are right to take precautions against it now rather than later."
What is Huawei and why is it being banned?
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