We don't know which song to be more excited about!

Keith Urban revealed a major new collaboration on his upcoming album, Ripcord, out May 6, in an interview with ET at the Academy of Country Music Awards: Carrie Underwood!

"I got Pitbull, and Carrie's on the record -- Carrie Underwood's on there, as well," the singer casually dropped on the red carpet.

WATCH: Keith Urban Opens Up About How Nicole Kidman Influenced His New Album, 'Ripcord'

The country stars each hit the ACMs stage for separate performances later that night. Urban delivered his newest single, "Wasted Time," while Underwood's "Church Bells" made its live television debut. They'll cross paths again later this week on the series finale broadcast of American Idol, where Underwood is among the show's many alumni on tap to perform. "I may even get to sing with one of them," Keith teased ET last month, without naming names. "Who knows? Stay tuned!"

No official word on whether Keith and Carrie could be preparing to join forces on stage, but we certainly wouldn't mind!

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Elsewhere on the album, Pitbull lends his signature sexy style on the track "Sun Don't Let Me Down," which was co-written and produced by living legend Nile Rodgers.

"It's about needing a few more hours of night to seal the deal. So, 'Don't come up, sun. Stay right where you are!' That's the gist of the song," Keith tells ET. "Who better than the sexy swagger of Pitbull to seal the deal? He was killer on it. I can't wait for people to hear it."

Turns out, Keith's wife, Nicole Kidman, is already a huge fan of the song!

"I definitely danced to that one," she gushed on the red carpet.

For more from our adorable interview with the duo, press play on the video below!

WATCH: Nicole Kidman Gushes Over Her Husband Keith Urban's Music, Makes Him Blush