Carrie Fisher was not in love with her 'Star Wars' co-star Harrison Ford, but she was infatuated with him.

Carrie Fisher

Carrie Fisher

The 60-year-old actress decided to lift the lid on her three-month fling with Harrison in her new memoir 'The Princess Diarist' - which details entries in her diary from 40 years ago - which occurred when they were shooting 'A New Hope' in London in 1976 and the then-33-year-old actor was married to Mary Marquardt.

The affair began after the pair - who played eventual lovers Princess Leia and Harrison Ford in the original trilogy - after attending a birthday party for the film's director George Lucas but fizzled out in a matter of weeks.

Carrie - who was 19 at the time of the tryst - doesn't think she or Harrison, now 74, had feelings strong enough to be described as love but she was very attracted to the screen heartthrob.

During an interview on 'The Ellen DeGeneres Show' she was asked by the host if they were in love, to which Carrie responded: "Well it depends on who you ask. I was infatuation, probably. Love is more mature."

Although the 'Star Wars' cast and crew were close, Carrie insists it was not hard for her and Harrison to hide their relationship from people.

She said: "I told other stuff to distract people so they wouldn't figure it out. No one thought it was happening at the time."

She jokingly added: "I don't even know if he did. No, he did."

Carrie believes she and Harrison - who were reunited in a galaxy far, far away in 2015 blockbuster 'Star Wars: The Force Awakens' - got together mainly because they were in the UK and lonely because they were away from their friends and family.

She told Ellen: "That's because everybody was away from home, so them the rules - I didn't know this. I was 19. No one told me about location rules, or lack of rules. But you can do whatever you want, as long as you film the movie. They can sleep together if their family's not around."