Arnold Schwarzenegger has paid a warm tribute to "comedy royalty" Ivan Reitman.

The 'Terminator' legend took to social media to reflect on the life of the 'Ghostbusters' director - who he worked with on movies such as 'Twins' and 'Kindergarten Cop' - following his passing at the age of 75 over the weekend.

Arnie described Ivan as a "mensch" - a term meaning a person of honour and integrity - and recalled how the filmmaker had a way of "making himself a part of your story".

Schwarzenegger wrote: "Ivan Reitman is a legend. In Hollywood, he was bigger than life. He was comedy royalty.

"In life, he was a mensch - a wonderful father and husband, a fantastic friend, a great human being. He was kind, he was generous, he was smart as hell, and he was always there for you.

"If you knew him, Ivan had a way of making himself a part of your story, and he certainly wrote a chunk of mine."

Arnie, 74, also explained that he owed the director a lot for giving him the chance to prove his worth as a comedy actor in Hollywood movies.

He said: "I'll always be grateful that he took a chance on this Austrian action-hero in a comedy during a time when the studios just wanted me to focus on finding new ways to kill bad guys, blow things up, and show off some muscles.

"I knew I could make it in comedy, but I needed someone else to know it to make it a reality."

The 'Total Recall' star concluded: "I can't believe I won't work with him again or hang out with him again or just schmooze about life again.

"But I also know that Ivan isn't gone, he's still with us. He's here, in so many pages of my story."