Francis Tuschek
LONDON — The head of MI5, Sir Ken McCallum, has issued a stark warning that Chinese state operatives pose a persistent and daily threat to the United Kingdom’s national security. Speaking publicly amid political fallout over a collapsed espionage case, Sir Ken revealed that MI5 had recently disrupted Chinese activities deemed harmful to national interests.
The remarks come as scrutiny intensifies over the Crown Prosecution Service’s (CPS) decision to drop charges against two men accused of spying for China—former parliamentary researcher Christopher Cash and academic Christopher Berry. The CPS concluded last month that the evidence did not meet the threshold for prosecution, a decision now under fire from across the political spectrum.
In his speech, Sir Ken acknowledged the frustration within the intelligence community when prosecutions fail, despite operational success in disrupting hostile activity. “Chinese state actors continue to challenge our national security,” he said, while emphasizing that broader diplomatic engagement with China remains a matter for government policy.
The controversy has reignited debate over the UK’s approach to China. Newly released witness statements from Deputy National Security Adviser Matthew Collins describe Beijing’s espionage efforts as “large-scale” and label China the “biggest state-based threat” to Britain’s economic security. Sir Ken praised Collins as a “man of high integrity,” reinforcing the credibility of the intelligence assessments.
The political fallout has been swift. Conservative leader Kemi Badenoch accused the government of sacrificing national security to preserve economic ties with China, writing to the Prime Minister that the decision “leaves a strong impression” of weakness. Downing Street rejected the claim, insisting the CPS acted independently and that it would have been inappropriate for the Prime Minister to intervene.
Labour leader Sir Keir Starmer responded by highlighting that the prosecution’s case hinged on the Conservative government’s stance on China between 2021 and 2023. He argued it was “plainly wrong” to suggest that China had been officially designated an enemy during that period.
CPS Director Stephen Parkinson has also come under pressure, reportedly telling MPs that the evidence fell just “5% short” of the threshold for a viable prosecution. Four parliamentary committee chairs have now demanded a detailed explanation for the decision to drop the charges.
Labour MP Emily Thornberry, chair of the Foreign Affairs Committee, expressed disbelief at the CPS’s caution, saying, “I can’t see that the jury would have had any problem deciding that China was a threat.”
The Joint Committee on the National Security Strategy, chaired by Labour MP Matt Western, has launched a formal inquiry into the matter.
The case centered on allegations that Cash and Berry collaborated with a senior Chinese Communist Party official linked to President Xi Jinping’s national security apparatus. In one message, Cash allegedly told Berry, “You’re in spy territory now.” Both men have denied wrongdoing.
Berry stated that his reports were intended for a Chinese company seeking trade opportunities and contained only publicly available information. Cash, in a separate statement, lamented the lack of a public trial to clear his name, calling the situation “impossible.”
China’s foreign ministry has dismissed the allegations, accusing the UK of “vilifying China” and promoting unfounded spy narratives.
As the political and legal fallout continues, the case has reignited concerns over how the UK balances national security with economic diplomacy—and whether the current system is equipped to confront the evolving threat landscape posed by foreign intelligence services.
