Andy Burnham says he is not embarrassed that he exchanged messages with a person posing as US President Donald Trump’s chief of staff.

The prime minister added all politicians face “these challenges” but insisted he did “everything right” in how he handled the security breach.

News website Politico first reported, external that Burnham communicated with a person claiming to be Susie Wiles. Burnham said there was a “minimal exchange of information of zero consequence”.

Liberal Democrat MP James MacCleary has written to Parliament’s Intelligence and Security Committee (ISC) to ask them to consider investigating what he called an “egregious security breach”.

It is understood the communication between Burnham and the person posing as Wiles was in the form of messages and there was no conversation between the two.

Asked if he was embarrassed about the incident, Burnham told broadcasters: “No, I am not because there was a minimal exchange, nothing of consequence and quickly I realised that this needed to be reported and I did so.

“So I handled it in the right way. All politicians are receiving these pressures and these challenges, but I did everything right.”

Pressed on what action is being taken to find out who was behind the incident and to improve systems, Burnham said the “correct action” had been taken both in the UK and the US, without providing further details.

MacCleary, in his letter to ISC chairman Lord Beamish, said the security of the prime minister’s communications “ought to be an absolute priority”.

He added: “We need to understand how this breach could occur, or else risk it being repeated.”

On Monday, Downing Street did not say when the messages were exchanged, or how many there were, nor whether they were over WhatsApp or another system.

A White House official told the BBC on Monday that the latest incident “had nothing to do” with Wiles’ phone being hacked.

The BBC previously reported an FBI probe into Wiles’ personal phone being hacked in May last year.

Wiles, a key Trump ally, told people at the time that her phone had been hacked after an impersonator – or impersonators – used her contacts file to message other top US officials.

Burnham is not the first high-profile UK political figure to have come into contact with an imposter.

In 2024, the Foreign Office confirmed then-foreign secretary Lord Cameron had been the victim of a hoax call in which someone pretended to be former Ukrainian President Petro Poroshenko.

Former Prime Minister Lord Cameron also exchanged some text messages with the impersonator pretending to be Poroshenko, who was president of Ukraine between 2014 and 2019.

The Foreign Office said it released details of the exchange publicly over fears it could be “manipulated”.

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