"It's never easy to lose such a vital, irreplaceable member of the family, but this is downright heartbreaking. Carrie was one-of-a-kind who belonged to us all- whether she liked it or not," Hamill said in a statement his rep released to ET on Tuesday night.
"She was OUR Princess, damn it, & the actress who played her blurred into one gorgeous, fiercely independent & ferociously funny, take-charge woman who took our collective breath away," the 65-year-old star continued. "Determined & tough, but with a vulnerability that made you root for her & want her to succeed & be happy."
"She played such a crucial role in my professional & personal life, & both would have been far emptier without her," he added.
Hamill and Fisher first shared the screen in the original Star Wars in 1977, playing Luke Skywalker and Princess Leia in roles that would forever make and define their careers. After appearing together in all three episodes of the original Star Wars trilogy, they reprised their iconic characters in Star Wars: The Force Awakens in 2015.
"I am grateful for the laughter, the wisdom, the kindness & even the bratty, self-indulgent crap my beloved space-twin gave me through the years," Hamill concluded. "Thanks Carrie. I love you."
Earlier in the day, Hamill took to Twitter to share his emotional reaction to the news of Fisher's death. The actor posted a black-and-white throwback photo of the pair in character as Luke and Leia in 1977, writing, "no words #Devastated."
Fisher died on Tuesday after going into cardiac arrest last week during a flight from London to Los Angeles International Airport. After receiving advanced life support from the paramedics, Fisher was relocated to a nearby hospital where she later died.
Many of Fisher's closest friends, co-stars and admirers took to social media after her death to share heartfelt tributes celebrating the beloved star's life and legacy. Watch the video below for a look at how some celebs honored the late actress.