Carly Rae Jepsen has been "sworn to secrecy" on the details of her impending duet with Justin Bieber.

The Call Me Maybe singer has been teasing fans about her collaboration with the teen heartthrob for months, but she is not going to reveal anything more just yet.

While Carly is resolute on not giving away any information on Justin, she is happy to spill the beans about the other tracks on her upcoming album which is due for release in September.

"The Justin song, I'm kind of sworn to secrecy on because I think we want to release it together at one moment," Carly explained to MTV News. "But the rest of the album, I'm really excited for."

Carly performs with a host of big name stars on the upcoming release, and is particularly excited about the track with LMFAO.

The 26-year-old has been writing music for almost a decade, so fans can expect to hear a range of emotions from when she was a 17-year-old angst-ridden teen.

"There's one particular song that I can't wait to share called This Kiss that I wrote with Matthew Koma and Redfoo from LMFAO, The sound [is] definitely in my vein,” Carly revealed. “I've been writing since I was 17, and to finally have an audience ready to hear some of that is really, really exciting for me.

"There's one or two song lyrics or melodies that have been taken from previous years.”