The Australian singer took to Twitter.com on Wednesday (11Jun14) to tell his fans he has spent some time collaborating with the Baby hitmaker on a new song.
He writes, "chill studio session last night with @justinbieber. wrote a beautiful guitar track. able to relate when it comes to love & women. good sht!"
Bieber also retweeted a photo taken by engineer-producer Josh Gudwin, which shows the two singers in the studio as Bieber intently listens to Simpson playing guitar.
The news comes months after Bieber revealed he worked with another teen singer, Austin Mahone, after the two met up at a recording studio in April (14).