Star Wars creator George Lucas has paid tribute to the late Carrie Fisher at a convention celebrating 40 years of the franchise.

Lucas took to the stage to make an emotional speech remembering a "one in a billion" actress at the Star Wars Celebration exhibition in Florida on Thursday.

"She played a part that was very smart, and she was having to hold her own against two big lugs, goofballs that were screwing everything up," the Star Wars creator said, referring to actors Harrison Ford and Mark Hamill.

"She was the boss. It was her war, and when I cast it, I said I want somebody young to play the part. I want somebody very young.

"When Carrie came in, she was that character," he added, remembering Fisher's first Star Wars movie when she was 19 years old.


Image: Star Wars' Carrie Fisher and director George Lucas pictured in 2005

"She was very strong, very smart, very funny, very bold, very tough, and there really wasn't much of a question. There are not very many people like her. They are one in a billion."

Before the director's speech, there was a video featuring footage of the actress, who died in December last year.

Fisher's daughter Billie Lourd shared a lesson her mother taught her as she introduced the video - which includes footage of the latest film in the sci fi franchise The Last Jedi.

"If life isn't funny, then it's just true, and that is unacceptable," she said.

This is so beautiful ❤ pic.twitter.com/5WSoIVG1Cm — Star Wars Stuff (@starwarstuff) April 13, 2017

Star Wars Celebration is a four day fan experience that includes panels, autograph signing sessions, merchandise stalls and exhibitions.

Lucas also recalled how Fisher was never afraid to contest his directorial decisions.

"She was very challenging in terms of pointing out that certain pieces of dialogue were a little hard to say," he told the audience.

"She was brilliant, and obviously we will all miss her, but she will always be the princess who took command and never backed down, never was in jeopardy. She was always helping the other guys get out of the messes she created.

"We'll all love her forever and ever."