Britain is already under attack in a new kind of conflict, one that doesn’t involve bombs or tanks, but rather cyberattacks, espionage, sabotage, and disinformation. That’s the stark warning from the House of Commons Defence Committee in a new report calling for urgent national action.
The report, Defence in the Grey Zone, warns that the UK is increasingly vulnerable to so-called “grey zone” threat, hostile state activity that falls below the threshold of conventional warfare but still causes significant harm to national security and everyday life.
Grey zone warfare encompasses a wide range of tactics, from the disruption of critical infrastructure and cyberattacks to political interference and propaganda. According to the committee, these threats are no longer theoretical, they are already happening.
“Grey zone threats bring war to the doorstep of each and every one of us,” said committee chair Tan Dhesi MP. “These attacks do not discriminate; they target the whole of our society and so demand a whole-of-society response.”
Threats Already on British Soil
The report highlights several recent incidents as evidence that Britain is already facing grey zone aggression, particularly from Russia and China.
In 2018, Russian military intelligence agents poisoned former double agent Sergei Skripal and his daughter in Salisbury using the Novichok nerve agent. A British woman, Dawn Sturgess, later died after secondary exposure.
In March this year, three men were convicted of carrying out an arson attack on a warehouse in east London that was supplying aid and communications equipment to Ukraine. Prosecutors revealed the attack was ordered by Russia’s Wagner Group, the private military company controlled by the Kremlin.
There are also ongoing concerns about surveillance of UK military sites by Russian operatives, while China has been accused of extensive espionage operations in the UK. In 2022, the Security Service issued an interference alert about Christine Lee, allegedly an agent of the Chinese Communist Party’s United Front Work Department, who had spent years lobbying British politicians. A year later, Chinese businessman Yang Tengbo was barred from entering the UK over allegations he was using a relationship with Prince Andrew to gather intelligence.
Vulnerable Infrastructure and a National Response
The Defence Committee’s report points to undersea communications cables, which carry 99% of UK data traffic, as a major vulnerability. It also stresses the threat to shipping lanes critical for both commerce and military operations.
Rather than relying solely on the armed forces, the committee urges the government to adopt a “whole-of-society” approach to national security. This would involve the Ministry of Defence working with schools, businesses, and local communities to raise awareness and improve resilience.
“While the armed forces have a key role to play, they can only be part of a wider national security strategy,” the report says.
Among the report’s recommendations are the creation of a dedicated homeland security minister, greater investment in the Joint Expeditionary Force (JEF), and the deployment of Royal Navy ships capable of extended Arctic operations.
The committee also calls for a stronger UK military presence in the Baltic Sea and a more strategic approach to countering threats from hostile states.
No Room for Complacency
The Defence Committee concludes that grey zone warfare is not a distant or emerging threat, it is an active campaign being waged against Britain and its allies now.
“At societal level, the Ministry of Defence should draw on its understanding of the threats faced to make a greater impact by proactively engaging far more with wider society,” the report urges.
While the UK is not formally at war with Russia or China, the report is clear: these governments are engaging in sustained activity designed to undermine British interests and national stability.
“Our adversaries have no illusions about their objectives,” it concludes. “We cannot afford to have any either.”
