Dominic Cummings’ Claims of Chinese Cyber Breach Rejected by Cabinet Office
Dominic Cummings has reignited debate over national security with bold claims that China accessed highly classified UK government information.
The former senior aide to Boris Johnson alleged in a recent interview that “vast amounts” of “extremely secret” intelligence data were compromised.
Cummings specifically pointed to high-level systems used to transfer Strap material, a classification reserved for the UK’s most sensitive intelligence.
He said, “Material from intelligence services. Material from the National Security Secretariat in the Cabinet Office.
Things the government has to keep secret. If they’re not secret, then there are very, very serious implications for it.”
The former strategist also suggested that the breach had been deliberately downplayed. “If the MPs want to finally have an inquiry about it, I’d be happy to talk about it,” he added.
Dominic Cummings has arisen from his sarcophagus yet again.
Cummings claims that China breached high-level systems used to transfer sensitive government information.Fair enough.
A reminder. Mr Cummings breached Covid rules without any shame whatsoever. #BBCBreakfast #GMB pic.twitter.com/wI1H1emuXx
— Alethea Bernard (@Tush27J) October 16, 2025
According to Cummings, he was briefed on the compromised data in 2020. He recalled a surreal moment during a briefing with senior officials: “The cabinet secretary said, ‘We have to explain something; there’s been a serious problem’, and he talked through what this was.
And it was so bizarre that, not just Boris, a few people in the room were looking around like this – ‘Am I somehow misunderstanding what he’s saying?'”
He went further: “What I’m saying is that some Strap stuff was compromised and vast amounts of data classified as extremely secret and extremely dangerous for any foreign entity to control were compromised.”
However, the Cabinet Office swiftly denied the claims. A spokesperson stated, “It is untrue to claim that the systems we use to transfer the most sensitive government information have been compromised.”
The controversy has drawn skepticism from cybersecurity experts. Professor Ciaran Martin, the first chief executive of the National Cyber Security Center, dismissed the allegations.
Speaking on BBC Radio 4’s The World Tonight, he said: “This is, to the best of my knowledge, categorically untrue. That would have fallen to the National Cyber Security Center to lead, and there was no such investigation.”
He emphasized that while China represents a “consistent and serious cyber security threat,” the UK’s Strap systems are fundamentally different from normal internet-based platforms.
“They’re built, monitored, secured, and operated in an entirely different way than normal internet-based systems.
It doesn’t follow that… they [China] can somehow penetrate these entirely bespoke systems and there wasn’t any evidence in 2020 that they did so.”
Cummings’s remarks raise pressing questions about transparency and oversight of the UK’s most sensitive digital networks. Critics argue that, if proven true, the claims would represent one of the gravest breaches in recent memory.