Lady Gaga's song-writing partner has teased a "mind-blowing" performance from the singer at the Oscars.
The Born This Way singer will be performing Til It Happens To You, her Oscar-nominated collaboration with Diane Warren from documentary The Hunting Ground, and Warren revealed even she does not know exactly what Lady Gaga has in store.
"Gaga delivers. Put her on a stage and she will blow you away. I can't wait to see what she does, I know it'll be mind-blowing," Warren vowed.
The Hunting Ground explores the topic of rape on US college campuses and both Warren and Gaga have spoken out about their experiences with sexual assault since the song was released.
Warren revealed that recording the song had been uncomfortable for Gaga.
"She's had her own experiences and it's been difficult for her, but I think this is healing.
"I think she had reservations at first about putting herself out there, but once she starting playing, it was so inspired and epic and it became something so powerful that neither of us saw (coming)."
Til it Happens To You has been viewed more than 26 million times online and sparked a 34 per cent increase in calls to the National Sexual Assault Hotline in the US, according to film-makers Amy Ziering and Kirby Dick.
"This song is waking people up, it's getting people to talk about it. I didn't talk about my own experience and then I blurted it out at a New York Times talk I did with Gaga. It even gave me the strength to talk about it," Warren admitted.
She said both herself and Gaga were receiving a "crazy number" of letters and emails from people "saying thank you for saving my life".
The pair will find out if that force for change translates into an Oscar win, and Warren believes the best original song category is one immune from the diversity debate that has plagued the ceremony.
She said: "May the best song win. I don't think you should win because you're white or black: you win because of your song, you're nominated because of your song."
The two are now back in the studio, working on material for Gaga's next album.
"We're already doing some really great stuff for her new album. I love working with her ... She's respectful. She'll push boundaries where she needs to push them but she'll always respect the material.
After Gaga's Super Bowl performance of the US national anthem, social media was aflutter with viewers surprised by how well she could sing - a sentiment Warren remembers only too well.
"I didn't realise she could sing like that either until she did a live performance a few years ago that blew me away. She's super talented and very trained. Her work ethic is insane, that's why she's going to be around," she said.