Major Chinese hacking operation 'tapped Downing Street phones' for years

State-sponsored Chinese hackers reportedly targeted the phones of the closest aides to Liz Truss, Rishi Sunak and Boris Johnson between 2021 and 2024.

One source said the breech went "right into the heart of Downing Street" - suggesting the prime minister's phones could have been compromised.

Intelligence sources in the US told The Telegraph that the espionage operation, known as Salt Typhoon, was ongoing.

Chinese spies may have been able to read text messages or listen to calls involving senior members of Government. They may have also accessed metadata, revealing who officials were in contact with and their geolocation.

This comes as Sir Keir Starmer will travel to China on Tuesday for the first prime ministerial visit to the country in eight years.

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The visit follows the approval of China's 'super-embassy' on the banks of the Thames - approval which saw concerns flagged over the security risks posed by such a project.

Alicia Kearns, a shadow minister for national security, said: : "How much more evidence does this Government need before it ends its simpering to Xi and stands tall as the great country we are and defends us?

"Labour is rewarding hostile acts against our state."

The data breaches go back to at least 2021, but intelligence agencies discovered them only in 2024. Salt Typhoon was exposed when the US found that hacking groups linked to Beijing had gained access to telecommunications companies around the world.

Ms Neuberger, who was deputy US national security adviser at the time, said hackers could "record phone calls at will".

China’s foreign ministry has previously said the claims were “baseless” and “lacking evidence”.

Intelligence sources told The Telegraph that telecommunications networks in Britain were better protected than those in the US.

They said the UK had been more “on the ball” about network security.

The sources cited the 2021 Telecommunications Security Act - which introduced new legal duties on the firms to strengthen UK network's security.

The FBI warned publicly last year that Chinese "state-sponsored cyber threat actors" were targeting global networks.

The advisory said the stolen data "ultimately can provide Chinese intelligence services with the capability to identify and track their targets’ communications and movements around the world".

It added that foreign actors often “maintain persistent, long-term access” to networks.

The public alert was co-signed by intelligence agencies from numerous countries, which includes the public-facing arm of GCHQ - the National Cyber Security Centre.

US officials have revealed the scale of the breach, admitting that Chinese hackers targeted Donald Trump, JD Vance and Kamala Harris in the run-up to the 2024 presidential election.

Peter Kyle, the technology secretary last year, said at the time that he "became very, very aware that there was a cybersecurity challenge that our country faced that I simply wasn’t aware of before becoming secretary of state".

Dakota Cary, a China-focused consultant at cybersecurity firm SentinelOne, told the paper: "Salt Typhoon has focused on telecommunications firms and the back-end of those networks so that they can pick up communications between individuals."

A spokesman for the Chinese embassy said: “China is a staunch defender of cyber security and one of the major victims of cyber espionage and attacks.

“We have been resolute in combating all kinds of malign cyber activities in accordance with the law, and never encourage, support or condone cyberattacks.

“We firmly oppose the practice of politicising cybersecurity issues or accusing other countries without evidence.”

LBC contacted Downing Street for comment.