Michael Douglas revealed on Sunday that fellow actor and friend Val Kilmer is battling oral cancer.

The actor was speaking at an event in London when the topic of his 1996 film, "The Ghost and the Darkness," which he filmed with Kilmer, came up in conversation.

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"The picture didn't turn out as well as I hoped, but I had a wonderful time," Douglas was quoted as saying. "Val was a wonderful guy who is dealing with exactly what I had, and things don't look good for him."

See photos of Val Kilmer through the years:

23 PHOTOS Val Kilmer through the years See Gallery Val Kilmer through the years WESTWOOD, CALIFORNIA - JULY 08: Val Kilmer (C) and guests attend the Monster Energy $50K Charity Challenge Celebrity Basketball Game at UCLA's Pauley Pavilion on July 08, 2019 in Westwood, California. (Photo by Vivien Killilea/Getty Images for Idol Roc ) WESTWOOD, CALIFORNIA - JULY 08: Val Kilmer attends the Monster Energy $50K Charity Challenge Celebrity Basketball Game at UCLA's Pauley Pavilion on July 08, 2019 in Westwood, California. (Photo by Allen Berezovsky/Getty Images) LOS ANGELES, CA - OCTOBER 26: Actor Val Kilmer attends Day One of The Los Angeles Comic Con held at Los Angeles Convention Center on October 26, 2018 in Los Angeles, California. (Photo by Jody Cortes/Getty Images) LOS ANGELES, CALIFORNIA - OCTOBER 26: Val Kilmer attends Los Angeles Comic Con at Los Angeles Convention Center on October 26, 2018 in Los Angeles, California. (Photo by Paul Butterfield/Getty Images) HOLLYWOOD, CA - JUNE 14: Director Eva Dolealová and actors Jack Kilmer and Val Kilmer attend an event where Flaunt Presents a private screening of Eva Dolezalova's "Carte Blanche" at Hollywood Roosevelt Hotel on June 14, 2018 in Hollywood, California. (Photo by Rich Polk/Getty Images for Flaunt) MIAMI BEACH, FL - DECEMBER 08: Val Kilmer, Tracey Emin, Jorge Perez, Jason Piszctatowski and Brett Sawyer attend 'The Last Ten Years: Tracey Emin in Conversation with Alastair Gordon' during Art Basel hosted by Soho Beach House in Miami Beach 2017 on December 8, 2017 in Miami Beach, Florida. (Photo by Andrew Toth/Getty Images for Soho House) MIAMI BEACH, FL - DECEMBER 08: Val Kilmer and Tracey Emin attend 'The Last Ten Years: Tracey Emin in Conversation with Alastair Gordon' during Art Basel hosted by Soho Beach House in Miami Beach 2017 on December 8, 2017 in Miami Beach, Florida. (Photo by Andrew Toth/Getty Images for Soho House) LOS ANGELES, CA - SEPTEMBER 17: (L-R) Tobey Maguire, Owen Wilson and Val Kilmer attend The Broad Museum Black Tie Inaugural Dinner at The Broad on September 17, 2015 in Los Angeles, California. (Photo by Jerod Harris/Getty Images) LOS ANGELES, CA - DECEMBER 25: Val Kilmer (L) and his son Jack Kilmer attend a basketball game on Christmas between the Golden State Warriors and the Los Angeles Clippers at Staples Center on December 25, 2014 in Los Angeles, California. (Photo by Noel Vasquez/GC Images) LOS ANGELES, CA - JANUARY 16: Val Kilmer (R) and his son Jack Kilmer attend a basketball game between the Cleveland Cavaliers the Los Angeles Clippers at Staples Center on January 16, 2015 in Los Angeles, California. (Photo by Noel Vasquez/GC Images) MIAMI BEACH, FL - DECEMBER 03: Peter Brant and Val Kilmer attend the Best Buddies Art + Friendship Auction at a private residence on December 3, 2013 in Miami Beach, Florida. (Photo by Dimitrios Kambouris/Getty Images for Best Buddies) SANTA MONICA, CA - SEPTEMBER 25: Actor Val Kilmer attends the 23rd annual Simply Shakespeare benefit reading of 'The Two Gentlemen of Verona' at The Eli and Edythe Broad Stage on September 25, 2013 in Santa Monica, California. (Photo by Jason LaVeris/FilmMagic) LATE NIGHT WITH JIMMY FALLON -- Episode 852 -- Pictured: (l-r) Actor Val Kilmer with host Jimmy Fallon during an interview on June 13, 2013 -- (Photo by: Lloyd Bishop/NBC/NBCU Photo Bank via Getty Images) AUSTIN, TX - NOVEMBER 02: Actor Val Kilmer acts on stage while filming the new Terrence Malick movie during day one of Fun Fun Fun Fest at Auditorium Shores on November 2, 2012 in Austin, Texas. (Photo by Rick Kern/WireImage) LOS ANGELES, CA - JANUARY 16: Val Kilmer (R) and his son Jack Kilmer attend a basketball game between the Cleveland Cavaliers the Los Angeles Clippers at Staples Center on January 16, 2015 in Los Angeles, California. (Photo by Noel Vasquez/GC Images) LOS ANGELES, CA - DECEMBER 25: Val Kilmer (L) and his son Jack Kilmer attend a basketball game on Christmas between the Golden State Warriors and the Los Angeles Clippers at Staples Center on December 25, 2014 in Los Angeles, California. (Photo by Noel Vasquez/GC Images) Val Kilmer arriving at the 'Red Dragon' world premiere at the Ziegfeld Theatre in New York City. September 30, 2002 . Photo by Evan Agostini/Getty Images Matt Dillon and Val Kilmer at the Lewis-Tyson Pre-Fight Party hosted by Showtime Networks at The Pyramid in Memphis, Tn. Saturday, June 8, 2002. Photo by Kevin Winter/ImageDirect. 404324 14: Actor Val Kilmer (L) and director D.J. Caruso attend the premiere of the film 'The Salton Sea' April 23, 2002 at the Egyptian Theatre in Hollywood, CA. (Photo by Vince Bucci/Getty Images) Val Kilmer and Nicole Kidman during 1995 ShoWest in Las Vegas, Nevada, United States. (Photo by Jeff Kravitz/FilmMagic, Inc) BEVERLY HILLS, CA - JANUARY 22: Actor Val Kilmer attends the 51st Annual Golden Globe Awards on January 22, 1994 at the Beverly Hilton Hotel in Beverly Hills, California. (Photo by Ron Galella, Ltd./WireImage) UNITED STATES - circa 1990: Actor Val Kilmer. (Photo by The LIFE Picture Collection/Getty Images) BEVERLY HILLS, CA - MAY 2: Actor Val Kilmer attends the Liberty Hill Foundation's Eighth Annual Upton Sinclair Awards on May 2, 1990 at the Beverly Hilton Hotel in Beverly Hills, California. (Photo by Ron Galella, Ltd./WireImage) Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

Douglas, of course, was alluding to his own battle with stage 4 oral cancer, which he successfully beat back in 2010.

"My prayers are with him," he continued. "That's why you haven't heard too much from Val lately."

Douglas' claims come just one year after Kilmer denied the rumors that he was battling some sort of illness in a strongly-worded Facebook post.

"Thank you all for your love and support," Kilmer said in October of 2015. "There's a rumor I'm unwell again and in hospital which is totally untrue. I was in to verify I have no tumor or infection of any kind which was verified by the very caring experts at UCLA."

Kilmer has yet to confirm or deny Douglas' new claims about his health.

See photos of Michael Douglas and his son through the years:



20 PHOTOS Michael Douglas and son Cameron Douglas See Gallery Michael Douglas and son Cameron Douglas HOLLYWOOD, CA - JUNE 25: Actor Michael Douglas and son Cameron Douglas arrive for the Premiere Of Disney And Marvel's 'Ant-Man And The Wasp' held at the El Capitan Theater on June 25, 2018 in Hollywood, California. (Photo by Albert L. Ortega/Getty Images) Actor Michael Douglas (L) and Cameron Douglas attend the World Premiere of Marvel Studios 'Ant-Man and The Wasp' at the El Capitan Theater, on June 25, 2018, in Hollywood, California. (Photo by Valerie MACON / AFP) (Photo credit should read VALERIE MACON/AFP/Getty Images) LOS ANGELES, CA - JUNE 20: Michael Douglas and his son, Cameron Douglas are seen on June 20, 2018 in Los Angeles, California. (Photo by BG002/Bauer-Griffin/GC Images) LOS ANGELES, CA - NOVEMBER 09: (L-R) Michael Douglas, Catherine Zeta-Jones and Cameron Douglas attend the Los Angeles Mission Legacy of Vision Gala at Four Seasons Hotel Los Angeles at Beverly Hills on November 9, 2017 in Los Angeles, California. (Photo by Tibrina Hobson/Getty Images) Â©2002 RAMEY PHOTO AGENCY EXCLUSIVE!!! New York 03/28/02 Michael Douglas & son Cameron Douglas pose after filming ' Smack In the Kisser', in Canal Street, Downtown Manhattan. 3-28-02 PG (Photo by Philip Ramey/Corbis via Getty Images) 404806 04: Actor Michael Douglas (R) and his son Cameron Douglas arrive at the Conde Nast Traveler Hot List party at the W Hotel May 1, 2002 in New York City. (Photo by Mark Mainz/Getty Images) Kirk Douglas, Anne Douglas, Diandra Douglas, Cameron Douglas, and Michael Douglas (Photo by Ron Galella, Ltd./WireImage) Michael Douglas, Cameron Douglas, and Diandra Douglas (Photo by Ron Galella/WireImage) Michael & Cameron Douglas during Holyfield v. Tyson II in Las Vegas, Nevada, United States. (Photo by Jeff Kravitz/FilmMagic, Inc) UNITED STATES - MAY 26: Diana Douglas Darrid with her grandson Cameron Douglas (l.) and her son Michael Douglas (r.) attending book party for Darrid's 'In The Wings: A Memoir' at Sardi's. (Photo by Richard Corkery/NY Daily News Archive via Getty Images) UNITED STATES - MARCH 15: Actors Lou Gossett Jr., Michael Douglas and son Cameron Douglas (l. to r.) watch as the New Jersey Nets defeat the Miami Heat, 97-78, at the Continental Airlines Arena. (Photo by Howard Earl Simmons/NY Daily News Archive via Getty Images) Michael Douglas, mother, and son Cameron Douglas (Photo by Jim Smeal/WireImage) NEW YORK - DECEMBER 17: (ITALY OUT) Cameron, Kirk and Michael Douglas stand in front of Cipriani's Restaurant December 17, 2002 in New York City, New York. (Photo by Arnaldo Magnani/Getty Images) LOS ANGELES - APRIL 7: Actor/producer Michael Douglas (L) and son actor Cameron Douglas arrive at the premiere of 'It Runs In The Family' at the Bruin Theater on April 7, 2003 in Los Angeles, California. (Photo by Kevin Winter/Getty Images) NEW YORK - APRIL 13: (U.S. TABS & HOLLYWOOD REPORTER OUT) (L to R) Diana Douglas, Kirk Douglas, Michael Douglas and Cameron Douglas arrive at the New York premiere of 'It Runs In The Family' at the Loews Lincoln Square Theater April 13, 2003 in New York City. (Photo by Scott Gries/Getty Images) Cameron Douglas and Michael Douglas (Photo by Mark Sullivan/WireImage) PROVIDENCIALES TURKS AND CAICOS ISLANDS, BWI- JANUARY 05: ***PREMIUM PRICING;USAGE IN POSITIVE STORY ONLY;GETTY IMAGES EXCLUSIVE;TABLOIDS OUT*** Actor Michael Douglas, actress Catherine Zeta-Jones with Cameron Douglas and his girlfirend Kelly Sotton Dellis Cay on Turk and Caicos while on holiday in the Caribean January 5, 2007 in Providenciales Turks and Caicos Islands. (Photo by Frazer Harrison/Getty Images). CULVER CITY, CA - MARCH 06: Cameron Douglas, actor Michael Douglas and actress Catherine Zeta-Jones attend Kirk Douglas' one man show 'Before I Forget' at The Kirk Douglas Theatre on March 6, 2009 in Culver City, California. (Photo by Jason LaVeris/FilmMagic) April 27, 2009 Hollywood, Ca.; Cameron Douglas and Michael Douglas; 'Ghosts of Girlfriends Past' World Premiere; Held at Grauman's Chinese Theatre (Photo by Gregg DeGuire/FilmMagic) Actor Michael Douglas and Cameron Douglas attend a performance of Hairspray on October 23, 2002 at the Neil Simon Theater in New York City. (Photo by Ron Galella, Ltd./WireImage) Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

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