Why Gwen Stefani Called Blake Shelton A 'F*cking A**hole'

In a new interview, Gwen Stefani opened up about why she called her boyfriend of more than four years, Blake Shelton, a "f*cking a**hole" over their new song. The stunning The Voice coach spoke out about a pretty candid conversation she had with Blake when he played her their upcoming new duet, titled "Nobody But You," for the very first time and why she initially wasn't very happy with him.

Speaking to Extra backstage at The Voice's semifinals on December 9, Gwen explained that she really wasn't so thrilled the first time she heard the track -- which was written by Shane McAnally, Ross Copperman, Josh Osborne, and Tommy Lee James -- because she thought Blake would be keeping it all for himself.

"Neither one of us wrote this song. It came to us, and when Blake heard it we were working out in the gym," Gwen explained while chatting to Renee Bargh, where she admitted that she didn't exactly have the nicest things to say to her boyfriend.

"He's playing the song and I'm like, 'You are such a f*cking a**hole. Everybody sings these incredible songs,'" she recalled.

"I am thinking in my brain, and I was like, 'God, I wish I was on this song…'" Gwen added.

But fortunately for the star, Blake was in fact about to ask her to duet with him on the track, which will feature on his brand new album, Fully Loaded: God's Country, set for release on December 13.

"He turns and says, 'God, I wish you were on this song,'" she shared of the moment he asked her to duet with him again, "and I was like, 'I was just thinking that!'"

"And he's like, 'I was just thinking that! You have to be on this song,'" she added, noting, "That's kind of how it happened."

Gwen chatted with the entertainment news outlet about the new song on The Voice set alongside fellow coach John Legend, who admitted during the interview that even he's pretty excited to hear the twosome team up once again but hasn't been lucky enough to get a sneak peek just yet.

"I'm dying to hear this song," he said.

Blake and Gwen have actually duetted twice before. The couple previously joined forces on the track "Go Ahead And Break My Heart," which featured on Blake's 2016 album If I'm Honest.

The two then collaborated once again on the festive hit "You Make It Feel Like Christmas" one year later, which was taken from Gwen's Christmas album of the same name.

As for "Nobody But You," Blake previously opened up about the song during a recent interview with The Tennessean.

He described the song as being "magical" and said he believes it's one of the most important songs he's ever recorded.

"I just think it's just timeless," he added.

The latest talk of new music from the couple comes shortly after the country star opened up about how he likes to listen to his older music because it reminds him of when he and Gwen first started dating.