The 'Baby I' singer has been in the studio with the controversial star - who is currently in rehab for anger management - and they announced their collaboration by sharing some of its lyrics on Twitter.
Chris tweeted: ''I dug a single seed into the ground, I hope it grows,''
Ariana responded: ''In a year or two if you're around, you'll see a rose.''
When asked what her favourite song at the moment is by a fan, Ariana teased: ''a song u haven't heard that is coming out in march (sic).''
The 20-year-old singer's manager, Scooter Braun, then confirmed the pair were teaming up, writing: ''@ArianaGrande that was an amazing session. Excited for this incredible duet on the way :) (sic)''
The song could help revitalise Chris' musical career, which has taken a back seat while he sorts out his personal issues, with his sixth album, 'X', still not on sale, despite four singles being released from it.
Chris, 24, has been on probation since his 2009 assault of then-girlfriend Rihanna, which was revoked last December, following an alleged assault in Washington D.C., a case which is still awaiting trial.
However, since attending rehab the 'Fine China' star's behaviour has improved, according to a report from his probation officer.
The report stated: ''The clinical and medical team have witnessed very positive change in Mr. Brown since his psychotropic medications have been changed and he has been taken off medical marijuana. His ability to emotionally regulate himself has improved markedly.''
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