LOS ANGELES, Sept. 20 (UPI) -- Justin Bieber and Sofia Richie have reportedly called it quits.
The 22-year-old Canadian singer and 18-year-old American model recently went their separate ways after a brief but highly-publicized romance, according to TMZ.
Sources told the website Bieber and Richie "were never all that serious to begin with" and are "moving on to see other people." Insiders made similar remarks about the short-lived couple to E! News.
"They were never officially together, but more casual hanging out and having fun," a source explained.
"It was super hot and heavy, and because Justin doesn't want a relationship right now, he wanted to cool things down," the insider added. "It wasn't an intentional cool-off. [It] just sort of happened on its own."
Bieber and Richie were first linked in early August and faced backlash for the relationship on social media. The pair were last seen on a tropical getaway to Cabo San Lucas, Mexico, for Richie's birthday in late August.
"We have a special relationship," the model had said in the Sept. 17 issue of Billboard. "Justin is very easy to talk to, and that's hard to find with people in Los Angeles.
Bieber will stay busy with his Purpose tour, which will come to a close Nov. 29 in London, England. Richie, the daughter of Lionel Richie and sister to Nicole Richie, was named the face of Madonna's Material Girl clothing line in July.