Why royal experts are worried about Prince Harry's tabloid lawsuits

Prince Harry is set to sue the publishers of Rupert Murdoch's Sun newspaper and the Daily Mirror over allegations of phone hacking as he and Meghan step up their warring with the press.

"Claims have been filed on behalf of The Duke of Sussex at the High Court regarding the illegal interception of voicemail messages," a spokeswoman for Harry said, declining to give further details of the claim.

A spokeswoman for News Group Newspapers, publisher of The Sun, confirmed that a claim had been issued by Harry.

Court documents first reported by website Byline Investigates also show that Harry is targeting Mirror Group Newspapers, owned by Reach PLC, with the legal action.

Reach Group declined to comment.

A source familiar with the situation said proceedings have been issued but the publisher is yet to receive legal papers in relation to the case.

On Tuesday Harry, Duke of Sussex, said he and his wife Meghan were taking separate legal action against the Mail on Sunday over the publication of a private letter that Meghan's lawyers said was "unlawful".

In a lengthy statement published on their website, Prince Harry said: "I lost my mother and now I watch my wife falling victim to the same powerful forces".

He described Meghan as "one of the latest victims of a British tabloid press that wages campaigns against individuals with no thought to the consequences" and said that he and Meghan were forced to take action against "relentless propaganda" by some sections within the media.

The couple also accused some sections of the British press of bullying behaviour.

The phones of Prince Harry, and brother William's wife Kate were hacked by staff working for Rupert Murdoch's now-defunct News of the World tabloid, a London court heard in 2013. News of the World had also been part of News Group Newspapers.

Now British journalists are afraid of how these actions will affect the future of royal reporting, especially when it comes to the royal power couple.

"This is very surprising," royal historian Robert Lacey told 9News. "It breaks precedent. The royal style is to take it on the chin.

"He's showing intense personal loyalty to his wife – but, some would say, at the expense of his real priorities."

"It's a pretty seminal court case for royal reporting, not just now but way into the future," royal commentator Camilla Tominey told the Today Show.

"I'm wondering whether there is a wisdom behind tarring all of the mainstream media with one brush."

"It's sad that it's come to this," royal commentator Dickie Arbiter told 9News.

"It's very sad that Harry has had a go at the British media, because it can have a negative impact – and I hope that in time he can find a way of healing the rift that now exists between him and the British media."

In the meantime, Harry and Meghan could soon be called to give evidence in court – the first members of the Royal Family to do so in more than a century.