The Duke of Sussex has lost a bid to have The Mail on Sunday publisher's defence to his High Court libel claim thrown out by a judge.
Harry, 39, is suing Associated Newspapers Limited (ANL) over an article published in February 2022 detailing his UK security arrangements.
On Friday, Mr Justice Nicklin ruled that the case must go to trial.
The judge concluded the publisher had a "real prospect" of successfully showing at a trial that previous Harry press statements provided a "misleading" description of his case against the Home Office.
A hearing dealing with the consequences of Mr Justice Nicklin's decision is expected to be held on Tuesday.
The Duke's lawyers have said the 2022 story, which claimed Harry "tried to keep details of his legal battle to reinstate his police protection secret from the public," was "an attack on his honesty and integrity" and would undermine his charity work and efforts to tackle misinformation online.
ANL is contesting the claim, arguing the article expressed an "honest opinion" and did not cause "serious harm" to his reputation.
The judgement comes after the High Court heard on Tuesday that Harry does not believe his children – Prince Archie, four, and Princess Lilibet, two – can "feel at home" in the UK if it is "not possible to keep them safe" there.
Harry's barrister, Shaheed Fatima KC, read out an excerpt from an emotional written witness statement prepared for his legal challenge.
The father-of-two explained why he and his wife, Meghan Markle, who live in Montecito, California, felt that they had to move to the US after stepping back as senior royals in 2020.
LISTEN: A Right Royal Podcast: saying goodbye to The Crown
Harry wrote: "It was with great sadness for both of us that my wife and I felt forced to step back from this role and leave the country in 2020.
"The UK is my home. The UK is central to the heritage of my children and a place I want them to feel at home as much as where they live at the moment in the US. That cannot happen if it's not possible to keep them safe when they are on UK soil."
He continued: "I cannot put my wife in danger like that and, given my experiences in life, I am reluctant to unnecessarily put myself in harm's way too."
Harry brought a legal challenge against the Home Office over the February 2020 decision of the Executive Committee for the Protection of Royalty and Public Figures (Ravec), after being told he would no longer be given the "same degree" of publicly funded security when in the UK.
The government says Harry’s claim should be dismissed, arguing that Ravec – which falls under the Home Office's remit – was entitled to conclude the Duke's protection should be "bespoke" and considered on a "case-by-case" basis.
LOVE THE ROYALS? JOIN THE CLUB!
If you are reading this, the chances are you are obsessed with all things royalty – which is just as well because so are we! So obsessed, in fact, we’ve launched a club solely dedicated to covering them. So welcome to The HELLO! Royal Club. We would love you to join us there…
What is it?
Interactive community offering behind-the-scenes access, exclusive royal interviews, unmissable royal insights, and an illustrious royal Inner Circle.
Two weekly newsletters, one from Emily Nash
Video posts and audio notes from Emily Nash and the HELLO! Royal team
Access to our royal community and opportunity to interact with club writers and members
Participate in polls, comments and discussion threads
Access to our Ask Me Anything sessions with our journalists
Invitations to in-person and virtual events
A subscription to the digital edition of HELLO! Magazine (Worth £82 annually)*
Future ‘Inner Circle’ benefits
By royal decree
You are royally invited to join The HELLO! Royal Club – and then to go forth and spread the word to your fellow royal fans. See you in the club!