MINISTERS fear China will unleash an online attack on Britain called a 'cyber-9/11' as tensions ramp up with Beijing.
Security sources believe the UK is faced with a "perfect storm" of rows over Hong Kong, the tech giant Huawei and Covid-19 - and it could lead to an attack by China-backed hackers.
The Government is preparing to announce plans to block Huawei from helping build the 5G mobile network.
Boris Johnson has also infuriated the Chinese Communist Party with his tough stance on Beijing’s clampdown on Hong Kong’s freedoms.
In addition, the PM has called for an inquiry into the true source of coronavirus.
Some claim it accidentally leaked from a Wuhan lab.
Now Brit security chiefs fear that, in a worst-case scenario, state-sponsored attacks would cripple computer networks, leading to phone and power blackouts and bringing hospitals, government and businesses to a halt, the Mail on Sunday reports.
And Tobias Ellwood, the chairman of the Commons defence select committee, says China poses more of a threat to the UK than Soviet Russia did during the Cold War.
He warned: "Any notion that China can be trusted must surely have been dispelled following its initial – and disastrous – attempts to conceal the Covid-19 pandemic.
"The way of life we take for granted is under real threat."
Australian Prime Minister Scott Morrison has briefed Mr Johnson on the risk posed by China after Australia was hit by a sustained large-scale cyber attack after taking a similarly hard line.
He says the attack last month targeted "government, industry, political organisations, education, health, essential service providers and operators of other critical infrastructure".
The Australian government hasn't publicly claimed China was responsible for the hacks.
However, it's understood officials concluded that the attack was linked to tensions with Beijing – despite China denying any involvement.
Britain’s National Cyber Security Centre says it is not "expecting" a rise in attacks.
But as Britain is poised to dramatically harden its relations toward China, Ministers believe there could be brutal retaliation.
One senior Minister told the paper: "Obviously this is part of our conversations.
"But at the same time, all risk must be looked at in the round.
"Actions, however, have consequences and they cannot be discounted."
And global strategist Dr Alan Mendoza from the Henry Jackson Society foreign policy think-tank added: "Far from being a benign friend, China is a strategic competitor with the means to strike at the heart of our infrastructure.
"China-proofing our critical systems must now become an urgent priority for the Government to avert a possible crisis."
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