Chinese state-sponsored hackers compromised the mobile phones of senior aides in Downing Street for several years, exposing private communications to Beijing, according to reports from The Telegraph.

The espionage operation, known as Salt Typhoon, targeted the phones of some of the closest aides to former prime ministers Boris Johnson, Liz Truss, and Rishi Sunak between 2021 and 2024. Breaches were particularly noted during Rishi Sunak's tenure from 2022 to 2024. A source familiar with the incident described the hack as penetrating 'right into the heart of Downing Street.'

British intelligence agencies discovered the intrusions in 2024. The full extent of the compromised data remains unclear, and officials believe the operation could still be active, posing risks to current Prime Minister Keir Starmer and his team. The hackers reportedly gained access through vulnerabilities in UK telecommunications networks, part of a broader global campaign targeting Five Eyes allies.

Salt Typhoon has been linked to Chinese state actors infiltrating telecom providers worldwide. In the United States, the FBI issued an alert warning that stolen data could allow Beijing to track targets' communications and movements. The campaign also affected U.S. officials and infrastructure.

The revelations emerged in late January 2026, just before Starmer's planned visit to China, the first by a British prime minister since 2018. They followed the UK government's approval of China's proposed mega-embassy in London, Europe's largest, amid concerns over increased Chinese diplomatic presence and potential spying via fibre-optic cables.

China has denied the accusations. A spokesperson from the Chinese embassy stated that Beijing is a 'staunch defender of cyber security' and a major victim of cyber espionage. The Foreign Ministry affirmed that China opposes hacking and rejects 'false information for political purposes.'

In response, the UK government sanctioned two Chinese tech firms last month for cyberattacks against Britain and its allies. MI5 issued an espionage alert to Parliament in November 2025, highlighting Chinese threats.

The incident underscores ongoing tensions in UK-China relations, with Westminster previously attributing other hacks to Beijing. Security experts have urged greater vigilance on mobile device protection, including the use of burner phones for sensitive communications.

No further public updates on the breach have surfaced since the initial reports two months ago, but the exposure highlights persistent vulnerabilities in government communications amid rising state-sponsored cyber threats.