Secret room to be built at Chinese embassy near cable lines, sparking widespread espionage fears

Recently unredacted construction plans for China’s new super embassy in London have ignited a storm of national security concerns across the United Kingdom, as blueprints reveal a hidden underground room positioned alarmingly close to some of Britain’s most sensitive communication cables.

Major critics of the proposed site, which will run as close as three feet to the internet infrastructure, warned that the secret room could serve as a hub for Chinese espionage. While the British government reportedly assured its allies that the lines do not carry sensitive government data, the cables transmit financial transactions as well as communication traffic for millions of internet users.  

The blueprints were publicly unredacted Monday by The Telegraph, just one week before Prime Minister Keir Starmer is widely expected to approve the plans before his visit to see President Xi Jinping in China.  

A government spokesman told the outlet that despite the security concerns, ‘national security is our first duty and government security experts have been involved throughout the process so far.’

According to the blueprint, the facility will be located at the former Royal Mint and will become Europe’s largest Chinese embassy. 

Construction plans indicate that China intends to demolish and rebuild a basement wall, placing officials and equipment just over three feet from critical fiber-optic cables. Security experts have warned that such proximity could create opportunities for ‘cable-tapping,’ which involves inserting wiretaps or reading light signals leaking from the lines.

Professor Alan Woodward, a security expert at the University of Surrey, highlighted the technical feasibility of espionage given the physical layout, The Telegraph reported. He described the demolition as a ‘red flag’ and noted, ‘If I were in their shoes, having those cables on my doorstep would be an enormous temptation.’

Additionally, the concealed chamber appears to be equipped with at least two hot-air extraction systems designed to ventilate heat-generating equipment. Experts reportedly inferred that this infrastructure suggests that the room is designed to accommodate high-powered technology such as advanced computers typically used for espionage and data processing. 

Beyond the single chamber near the cables, the unredacted plans also revealed a network of 208 secret rooms beneath the diplomatic site. The basement appears to allow for emergency backup generators, sprinkler systems, communications cabling and showers, suggesting that officials could remain underground for extended periods, potentially to operate or monitor equipment.

The construction plans have generally raised fears that the London complex could serve as a Beijing intelligence hub. According to U.K. outlet The Times, Britain has been pressured to reassure the United States and other intelligence partners that the cables do not transmit any sensitive government data.

Alicia Kearns, the shadow national security minister and prominent critic of the project, described the approval of the embassy as handing Beijing a strategic advantage against British interests.  

‘Giving China the go-ahead for its embassy site would be to gift them a launchpad for economic warfare at the very heart of the central nervous system of our critical financial national infrastructure,’ she said in a post on X.