The PM is said to have become suspicious by the messages(Image: Getty Images)

The Prime Minister allegedly spoke to someone pretending to be one of Donald Trump's top advisers, it is reported.

Andy Burnham, who only became PM late last month on July 20, is said to have engaged with messages sent by someone 'impersonating' Susie Wiles, the White House's chief of staff.

Reports have said Burnham communicated with the messages but became suspicious, with UK officials fearing Ms Wiles had possibly been hacked.

According to Politico, a person told the outlet a "few messages" had been exchanged after the PM entered Downing Street but stressed they were "of no significance".

It is unclear what was in the content of the messages as Downing Street declined to comment. “We do not comment on national security matters,” a No10 spokeswoman said, The Mirror reports.

The British embassy in Washington, DC, has reportedly raised the matter with the White House.

US media reports the FBI and the White House probed reports of someone pretending to be Ms Wiles last year. The Wall Street Journal reported last May that senators, governors, top American business chiefs and other well-known figures had received communications from someone saying they were her.

“The White House takes the cybersecurity of all staff very seriously, and this matter continues to be investigated,” a White House spokeswoman said at the time.

The matter comes as Mr Burnham will be hoping to smooth out relations with the US after Trump slammed former PM after Keir Starmer voiced disagreement with the joint US-Israel strikes on Iran in February.