British PM Andy Burnham exchanged messages with someone impersonating Trump’s chief of staff

Britain’s Prime Minister Andy Burnham exchanged messages with someone impersonating the White House chief of staff Susie Wiles, who is one of US President Donald Trump’s closest advisers, a source with knowledge told CNN.

It’s unclear when the exchange happened or what was discussed but Politico, which first reported the breach on Monday, said the British embassy in Washington was so concerned it raised the incident with the White House.

Downing Street told CNN it does not comment on national security matters.

CNN understands that the communication was in the form of messages and “no messages of significance” were exchanged; Burnham quickly became suspicious, and the incident was reported to the proper authorities.

Burnham became Britain’s prime minister on July 20, but was effectively the country’s prime minister-in-waiting for a month prior to that when he re-entered parliament.

“This incident had nothing to do with the Chief of Staff’s devices being hacked,” a White House official told CNN.

Phishing attempts have continued with people associated with Wiles in recent months after an incident in May 2025 when US law enforcement launched an investigation into efforts to impersonate her.

A senior White House official said at the time that Wiles told others in the Trump administration she believed her personal phone and contact list had been hacked, as the impersonator only contacted high-profile people on that list.

Many of the people – including business executives, senators and governors – who received messages were skeptical they were from Wiles, according to the official.