Rishi Sunak has declined to comment on the impact on the royal family from the revelations that have emerged so far from the Duke of Sussex and his forthcoming memoir.
The Prime Minister was visiting Harris Academy secondary school in south-west London on Friday when he was asked about the claims made by Prince Harry in Spare.
Mr Sunak, 42, was also asked about Harry's claims that he killed 25 people as a helicopter pilot during his time in Afghanistan.
Watch the video below to see the Prime Minister's comments.
Harry, 38, writes in his book that in the heat of the combat he did not think of the 25 as "people" but instead as "chess pieces" that had been taken off the board.
In extracts shared by The Telegraph, Harry said: "So, my number is 25. It's not a number that fills me with satisfaction, but nor does it embarrass me."
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Prince Harry serving in Afghanistan in 2008
Harry carried out two tours of Afghanistan during his ten-year army career – first in 2007 and the second time in 2012.
The Duke's comments have done little to endear him to military top brass, with one retired British Army colonel saying Harry has turned against his "other family, the military".
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Colonel Tim Collins, known for a pre-battle speech he made in Iraq, told Forces News on Friday: "Amongst [Harry's] assertions is a claim that he killed 25 people in Afghanistan.
"That's not how you behave in the Army; it's not how we think."
Col Collins later added: "Harry has now turned against the other family, the military, that once embraced him, having trashed his birth family."
Among the Duke's bombshell revelations in his book are details of a physical fight between him and his older brother, Prince William, and accusations that his stepmother, Queen Consort Camilla, leaked stories to the press.