Prince Harry plans to support his father King Charles III as much as he can as the monarch undergoes cancer treatment.

While he was in Canada last week for the Invictus Games Vancouver Whistler 2025's One Year to Go celebrations, the Duke of Sussex opened up about his father's cancer diagnosis and his recent trip to the U.K. to visit the King during an interview with "Good Morning America's" Will Reeve.

Prince Harry told Reeve that after learning about King Charles' condition, he "jumped on a plane" and flew to London to see his father as soon as he could.

The royal, who stepped back from royal duties and moved to California in 2020, added that he was "grateful" for the time spent with the monarch during his brief visit.

King Charles and Prince Harry
(Photo : Matt Dunham - WPA Pool/Getty Images)
Prince Harry and Prince Charles, Prince of Wales arrive to attend the 'International Year of The Reef' 2018 meeting at Fishmongers Hall on February 14, 2018 in London, England.

"Look, I love my family. The fact that I was able to get on a plane and go and see him and spend any time with him, I'm grateful for that," the duke said.

Prince Harry refused to share his outlook on the state of King Charles' health, telling Reeve: "That stays between me and him."

But the Duke of Sussex agreed that the health situation could "absolutely" have a "reunifying effect" on the royal family.

"Throughout all these families, I see it on a day-to-day basis, the strength of the family unit coming together," Prince Harry said of connecting with Invictus Games competitors and their families.

The royal continued, "So, yeah, I think any illness, any sickness, brings families together. I see it time and time again, and that makes me very happy."

According to the former military pilot, while he now has his life in California, where he and his family reside, he plans to visit King Charles again during his upcoming trips to the U.K.

"I have my own family, as we all do. My family and my life in California is as it is," Prince Harry explained. "I've got other trips planned that would take me through the U.K. or back to the U.K., so I'll stop in and see my family as much as I can."

Prince Harry was spotted in London on Feb. 6, just a day after Buckingham Palace publicly announced that King Charles was diagnosed with cancer and had begun undergoing treatment.

People reported that King Charles personally told Harry and his older brother, Prince William, about the diagnosis before it was made public.

The father and son reportedly had a brief private meeting at Clarence House, King Charles and Queen Camilla's London residence.

This marked Prince Harry's first face-to-face reunion with the monarch since King Charles' coronation ceremony in May last year.

Prince Harry
(Photo : Joern Pollex/Getty Images for Invictus Games Düsseldorf 2023)
Prince Harry, Duke of Sussex makes a speech during the closing ceremony of the Invictus Games Düsseldorf 2023 at Merkur Spiel-Arena on September 16, 2023 in Duesseldorf, Germany.

The Duke of Sussex flew back to the U.S. just a day later and made a surprise appearance at the NFL Honors ceremony in Las Vegas on Feb. 8.

Last week, Prince Harry and Markle headed to Canada for the 2025 Invictus Games countdown celebrations.

The couple spent Valentine's Day on the slopes at Whistler, British Columbia, where competitors held a winter training camp.

The Sussexes wrapped up their three-day Canada trip by attending the One Year to Go Dinner at Vancouver Convention Center.

Meghan Markle, Duchess of Sussex and Prince Harry, Duke of Sussex
(Photo : Getty Images/Andrew Chin)
(L-R) Meghan, Duchess of Sussex and Prince Harry, Duke of Sussex attend Invictus Games Vancouver Whistlers 2025's One Year To Go Winter Training Camp on February 14, 2024 in Whistler, British Columbia.