Meanwhile, it was previously revealed that Harrison's iconic character Han Solo will still have a major part in 'Star Wars: The Last Jedi', despite being shockingly murdered by his own son Ben Solo/Kylo Ren (Adam Driver) in the 2015 movie 'The Force Awakens'.
Director Rian Johnson said: "A figurative ghost of Han had to be present throughout this entire film.
"Kylo has definitely been knocked off base. The defeat that he had at the end of 'The Force Awakens', but even bigger than that, his huge defining act which, spoiler alert, is the murder of his father... that's the more interesting thing to dive into.
"How has he dealt with that in his head? Where is he at in terms of that act and what does that mean for him?"
The filmmaker also confirmed that Han Solo's long-time companion Chewbacca has a new mission.
He said: "Chewie's doing all right. It's tough. It was obviously a big loss for him, but, you know, he's Chewie. He's resilient.
"He's got broad Wookiee shoulders, and he also has a new mission. He's got Rey, and she's someone that Han, to a certain extent, handed the keys to. So I think that helps."
Daisy Ridley - who plays the parentless hero Rey - also said her character cannot understand Kylo's actions.
She said: "She just doesn't understand Kylo. When all she wanted was parents, why would a person who has parents do that?
"It's so beyond comprehension, it's ridiculous. So she has grief for the loss and then there's anger. To be honest, she couldn't understand doing something like that - let alone to your parents."
