China Hacked Downing Street Phones for Years

China conducted a long-running cyber-espionage operation targeting Downing Street, compromising the mobile phones of senior UK government officials, according to an exclusive investigation by The Telegraph.

The spying campaign is understood to have penetrated deep into the heart of government, with private communications potentially exposed to Beijing. One source familiar with the breach said the operation reached “right into the heart of Downing Street.”

Senior Aides Targeted

State-sponsored hackers are believed to have targeted aides to former prime ministers Boris Johnson, Liz Truss and Rishi Sunak between 2021 and 2024. It remains unclear whether the mobile phones of the prime ministers themselves were directly compromised.

US intelligence sources said the operation, known as “Salt Typhoon,” was ongoing, raising concerns that current Prime Minister Sir Keir Starmer and his senior staff may also have been affected.

Security Warnings and Political Fallout

MI5 issued an espionage alert to Parliament in November, warning of increased Chinese spying activity. The revelations come as Sir Keir prepares to travel to China this week — the first visit by a UK prime minister since 2018 — in an effort to strengthen trade and investment ties.

The trip follows the government’s approval of plans for a major Chinese embassy in London, which The Telegraph reported would be built near some of the City’s most sensitive communications infrastructure.

Data Exposure Risks

Security experts warn the breach may have allowed Chinese intelligence services to read text messages, listen to calls, or access metadata. Even without full interception, such data could reveal officials’ contacts, communication patterns and approximate locations.

The Downing Street breach was part of a broader global espionage campaign targeting several countries, including the United States and other members of the Five Eyes intelligence alliance: Australia, Canada and New Zealand. Although the attacks began as early as 2021, intelligence agencies only identified them in 2024.

Calls for Tougher Response

Alicia Kearns, a shadow minister for national security and one of the alleged targets in a related Westminster spying case, accused the government of failing to respond firmly to hostile actions by Beijing.

“How much more evidence does this Government need before it stands tall and defends us?” she said, warning that prioritising trade risks undermining national security.