Justin Bieber and Ariana Grande

The secret is out. Two of music’s biggest pop stars, Justin Bieber and Ariana Grande, are teaming up for a duet.

Rumors started after Bieber posted an Instagram photo of him in the studio with the Nickelodeon star. “congrats @arianagrande on your number 1 song. #arianabieberduet ??” he said.

After it became a trending topic, Ariana confirmed the rumors, tweeting, “thank u justin!! secrets out now.”

Their collaboration could appear on Ariana’s sophomore album, due in August. The follow-up to last year’s Yours Truly features production from Zedd, Benny Blanco, Ryan Tedder, Key Wane, and Rodney Jerkins.

Meanwhile, her single “Problem” featuring Iggy Azalea is expected to make a big debut on next week’s Billboard Hot 100 after selling over 300,000 downloads. A video was recently shot in L.A. with Iggy and Big Sean.