Olivia Wilde explains why she dedicated The Invite to late co-star Diane Keaton

Olivia Wilde has explained why she dedicated her new movie The Invite to her late co-star Diane Keaton.

In her third directorial outing, Wilde and Seth Rogen play a couple in crisis who invite their neighbours (Edward Norton and Penélope Cruz) over for a dinner party.

Before the credits roll, the message, "For Diane," flashes up on the screen, and Wilde explained to The Hollywood Reporter that she wanted to honour her Love the Coopers co-star, who died in October.

"I really wanted to show this movie to Diane. I don't think that there is an Invite without Diane Keaton because she's in so many of the films that inspired this film," Wilde told the outlet at The Invite's Los Angeles premiere. "She is the first actress I recognised to kind of represent a totally unique and complex woman; she didn't fit any archetype, she was singular in her vulnerability, her complexity, her creativity."

The Booksmart director added, "She's unlike anyone else and she was very encouraging to me personally, and I just wanted this to be for her."

Keaton, who played the star's mother in the 2015 Christmas comedy, passed away in October at the age of 79 after a period of failing health. Her cause of death was listed as bacterial pneumonia.

After her death, Wilde recalled working with Keaton on Love the Coopers - also known as Christmas with the Coopers - in a lengthy tribute on Instagram.

"She laughed through night shoots, kept us roaring with laughter constantly actually, and talked to us for hours about love," she wrote. "She told me to keep my heart open. She told me to direct. She told me to be brave. She told me to keep laughing."

The Invite, an English-language remake of the Spanish film The People Upstairs, is in U.S. cinemas now. It will be released in the U.K. on 3 July.