Actor Jake Gyllenhaal says late star Heath Ledger "refused" to participate in an Oscars opening act on being told that he'd be poking fun at the gay romance in their film "Brokeback Mountain".

The two stars played Jack Twist and Ennis Del Mar in the Ang Lee-directed film, which follows the unexpected romance between two men.

Gyllenhaal recalled how Ledger stood his ground while talking to Another Man magazine, telling them that the actor didn't find anything funny about the heart-wrenching love story between two cowboys, reports dailymail.co.uk.

"That's the thing I loved about Heath. He would never joke. I remember they wanted to do an opening for the Academy Awards that year that was sort of joking about it," Gyllenhaal told the magazine.

Ledger thought the jokes mocked the message of the film, refusing to participate in the segment.

"Heath refused," he said, then recalling how he didn't exactly understand Ledger's reasoning.

He added: "I was sort of at the time, 'Oh, okay… whatever, it's all in good fun'. And Heath said, 'it's not a joke to me -- I don't want to make any jokes about it'. That's the thing I loved about Heath. He would never joke. Someone wanted to make a joke about the story or whatever, he was like, 'No. This is about love'."

Heath still ended up attending the awards, however, and was seen at the ceremony with girlfriend and co-star Michelle Williams.

"Brokeback Mountain" was a success. It earned eight Oscar nominations, including Best Picture and acting nods for both Ledger and Gyllenhaal. The film earned director Ang Lee a Best Director honour.

Ledger passed away in 2008 after an accidental overdose of prescription drugs.