Documents have been filed on behalf of Prince Harry over the alleged illegal interception of voicemail messages, the BBC quoted Buckingham Palace has confirmed as saying on Friday.
His wife Meghan Markle this week began legal action against the Mail which is accused of unlawfully publishing a private letter to her father.
A spokeswoman for News Group Newspapers (NGN) - the publishers of the Sun and the News of The World - said: "We confirm that a claim has been issued by the Duke of Sussex."
A source at Reach, which owns the Mirror, told the UK's Press Association that it was aware proceedings had been issued but had not yet received them.
The Duke's fresh legal claim comes just days after he accused the British tabloid press of "relentless propaganda" in his statement announcing his wife's legal action.
In the statement, which was issued during the couple's tour of southern Africa, Prince Harry said the "painful" impact of intrusive media coverage had forced them to take action.
Referring to his late mother Diana, Princess of Wales, the prince said his "deepest fear is history repeating itself".
"I've seen what happens when someone I love is commoditised to the point that they are no longer treated or seen as a real person," he said.
( With inputs from IANS )