The claims against the Daily Mirror and The Sun were filed in the High Court of Justice on Harry's behalf and involve "illegal interception of voicemail messages," Buckingham Palace confirmed on Saturday to The Associated Press.
The announcement comes four days after Harry's American wife Meghan Markle filed a claim against the Mail on Sunday and its parent company Associated Newspapers, alleging "the intrusive and unlawful publication of a private letter" written by the Duchess of Sussex. The Guardian reported that the letter was penned by Markle to her estranged father.
The Sun is owned by News Group Newspapers, a subsidiary of News Group -- which is a sister company of Fox Corporation, which owns Fox News Group. The newspaper acknowledged Harry's legal action. Reach plc, which owns the Daily Mirror, said it was "aware that proceedings have been issued" but hasn't yet received notice of them.
On Tuesday, Harry issued a statement condemning the "British tabloid press" for running a "ruthless campaign" against his wife "that has escalated over the past year."
"Up to now, we have been unable to correct the continual misrepresentations -- something that these select media outlets have been aware of and have therefore exploited on a daily and sometimes hourly basis," Harry noted.
The prince also said his "deepest fear is history repeating itself."
"I’ve seen what happens when someone I love is commoditized to the point that they are no longer treated or seen as a real person. I lost my mother and now I watch my wife falling victim to the same powerful forces," he said in a reference to his mother, Princess Diana, who died in a 1997 car crash while trying to elude paparazzi in Paris.
British tabloid newspapers have paid millions of dollars to settle claims that their employees had hacked the phone voicemails of celebrities, politicians and others in the public eye.
Harry and William have long had a strained relationship with the press. They grew up in the spotlight and were young boys when their parents' acrimonious divorce received wall-to-wall coverage.
Fox News' Mariah Haas and The Associated Press contributed to this report.