The final instalment of the mainline 'Star Wars' series will be subtitled 'The Rise of Skywalker'.

The film - which was previously known as 'Star Wars: Episode IX' - released its first trailer on Friday (12.04.19), and with it, the full title of the project was announced as 'Star Wars: The Rise of Skywalker'.

The trailer aired at the annual 'Star Wars' Celebration event in Chicago, and was introduced by director Jj Abrams, producer Kathleen Kennedy and key cast members including Daisy Ridley, John Boyega, and Kelly Marie Tran.

Footage in the trailer showed Daisy's character Rey hugging John's Finn, as well as wielding a lightsaber, dodging explosions and being told by Mark Hamill's gravelly voiceover as Luke Skywalker that the future rests on her shoulders and that ''no one is really gone''.

'The Rise of Skywalker' is set to bring an end to the nine-part mainline film saga, although further spin-off movies are still in development.

During the event, JJ confirmed the final film unfolds after the events of eighth instalment 'The Last Jedi', and teased a ''great'' storyline.

He said: ''Some time has gone by. This is an adventure that the group goes on together. It's a story that I think is one of the great things about the movie - the dynamic between the characters. They are just the most wonderful together.''

The film will also feature an appearance from the late Carrie Fisher - who passed away in 2016 - whose character Princess Leia will be implemented into the movie using discarded footage from the first two films in the new trilogy.

JJ said: ''Princess Leia lives in a way in this film that is kind of mind-blowing to me. You don't recast that part and you don't suddenly have her disappear. The idea of having a CGI character was off the table. So we said 'What if we could write scenes about her so it's her performance?'

''Every day it hits me that she's not here. It's so surreal because we are working with her still, if that makes sense. She's in scenes. She's alive in scenes.''

'Star Wars: The Rise of Skywalker' is set to hit cinema screens in December.