Why he’s fighting. Prince Harry hasn’t held back in his ongoing fight against the Daily Mirror — and an insider says that’s not about to change.

“Harry’s hell-bent on winning this case, no matter what,” the source exclusively reveals in the new issue of Us Weekly. “Harry says he’ll share whatever he must to bring justice. He’s willing to risk it all in that regard.”

The Duke of Sussex, 38, began his testimony in the case earlier this month, appearing in court on June 6 and 7. The Spare author is suing Mirror Group Newspapers, which publishes the Daily Mirror, for allegedly gathering information about him by unlawfully accessing his voicemail messages between 1996 and 2011. The media company, meanwhile, has denied the claims by stating that its journalists used legal reporting techniques.

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Prince Harry.
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“It’s been extremely draining and nerve-racking,” the insider says of Harry’s involvement in the case. “But Harry’s determination to speak up against what he claims was plain illegality is what pushed him through and kept him focused.”

In his witness statement, the Invictus Games founder blamed tabloid coverage of his personal life for his split from Chelsy Davy, whom he dated off and on from 2004 to 2010. The U.K. native alleged that reporters tracked his and Davy’s whereabouts via voicemails, which led to their outings being interrupted by photographers and journalists.

“Ultimately, these factors led her to make the decision that a Royal life was not for her, which was incredibly upsetting for me at the time,” Harry wrote, noting that he and Davy, 37, frequently communicated by phone because they were often living in different countries.

Prince Harry
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The prince also detailed “unusual mobile activity” he noticed over the years, claiming that the “new voicemail” symbol would sometimes disappear before he had a chance to listen to the message. “I don’t know how long after they’d been listened to that the symbol vanished, presumably straight away,” he wrote. “I also distinctly remember people saying to me ‘did you not get my voicemail?’ on both a personal and a work-related level. I was like, ‘no,’ and sometimes I would go back into my voicemail to look for it but still couldn’t find it.”

Harry has already faced pushback from Mirror Group attorney Andrew Green, who questioned him during the first two days of testimony. When the former military pilot theorized that his school landline could have been hacked while he was talking to his late mother, Princess Diana, Green replied, “That’s just speculation you’ve come up with now.”

While Meghan Markle hasn’t accompanied her husband to the court proceedings, the source notes that the Suits alum, 41, has been Harry’s “rock” during the ordeal. “She’s proud of him for having the strength and courage to do the right thing,” the insider tells Us.

For more on Harry’s court battle, watch the video above and pick up the new issue of Us Weekly, on stands now.