Olivia Rodrigo has confessed to a girl crush on Cardi B after revealing the rapper gives her the courage to say whatever is on her mind.

The Drivers License star has made it clear she's a big Taylor Swift fan and in a new Apple Music interview she has now gushed about the Bodak Yellow hitmaker, admitting she'd like to marry Cardi B.

"I'm so in love with her. I want to marry her," Rodrigo said.

"I'm obsessed with her. I love (album) Invasion of Privacy," she continued.

Rodrigo went on to congratulate Cardi for the success of her latest single, Up, saying she felt "so stoked for her" and "literally almost cried" when the track hit the top of the U.S. charts.

"I feel lucky to be a teenager at the time when Cardi is making music," she shared.

"As a songwriter, some of the stuff that she says is just so honest and almost like, shockingly honest. When I listened to her song, I'm like, 'Oh wow, she really just said that on a recorded album'," the singer marvelled.

"Those are my favourite artists, who say stuff that other people are scared to say. I think(Cardi) does that so well," she reflected, admitting: "That's definitely something that I sort of grapple with in my songwriting. I'm making a lot of music right now to put it out, and I listen to it back and I'm terrified sometimes."

Confessing: "I'm like, 'Oh my God, I literally am writing about stuff that I don't tell some of my closest friends, and I'm going to put it out for the whole world to scrutinise and talk about'," Rodrigo said: "She gives me courage to sort of say whatever I want to say and be honest in telling my story."

Cardi caught the interview and responded on social media, calling Olivia "such a sweetie pie" and revealing she's a fan, enthusing: "I can’t wait to see what she have coming next! (sic)"