British Prime Minister Andy Burnham has exchanged messages with someone impersonating White House chief of staff Susie Wiles, in a security breach that was reported to the authorities.
The exchange was first reported by Politico, which cited four officials, and was subsequently confirmed by the BBC. Downing Street declined to discuss the incident, with a No 10 spokeswoman saying: “We do not comment on national security matters.”
One person briefed on the contact said only a few messages had been sent and that they were “of no significance”. Burnham grew suspicious during the conversation and the matter was passed to the relevant authorities, officials said.
The messages were sent after Burnham entered Downing Street on July 20. What was discussed, and who was behind the account, remains unknown.
The British embassy in Washington raised the matter with the White House, two officials said. British officials feared the phone used by Wiles, one of US President Donald Trump’s closest advisers, had been compromised for a second time.
Wiles’ personal mobile was accessed in May 2025 and her contacts used to send messages and make calls to US senators, governors and business chiefs, according to The Wall Street Journal. The FBI opened an investigation and some recipients said the voice they heard appeared to have been generated by artificial intelligence.
Wiles was also among those targeted in 2024 by a cyber-espionage operation linked to Iran’s Islamic Revolutionary Guard Corps.
European officials have been drawn into comparable operations. In June 2025 an unknown actor used an AI-generated version of the voice of US Secretary of State Marco Rubio to contact three foreign ministers, a US governor and a member of Congress through the Signal messaging app, according to a State Department cable dated July 3 that year.
Polish foreign minister Radosław Sikorski was filmed in a video call with Russian pranksters posing as former Ukrainian president Petro Poroshenko, footage of which was released in 2024. Then-British foreign secretary David Cameron fell for the same ruse in June that year, exchanging texts and holding a brief video call before the Foreign Office declared it a hoax.
Burnham took office after Keir Starmer resigned and has promised a closer relationship with the EU, with an EU-UK summit expected in the autumn. He spoke to Trump by telephone for 20 minutes on the day he entered Downing Street, in a call his office described as very warm.
