Justin Bieber 'denies Selena Gomez cheated with Zayn Malik'

Justin Bieber has reportedly denied he wrote comments on social media accusing Selena Gomez of cheating on him with Zayn Malik.

The former lovers fell out after she took aim at the Baby singer for threatening to quit Instagram over vile remarks made about his teenage girlfriend Sofia Richie.

"I'm gonna make my Instagram private if you guys don't stop the hate this is getting out of hand. If you guys are really fans you wouldn't be so mean to people that I like," he captioned a black and white Instagram shot of himself and 17-year-old Richie.

In a now-deleted post Selena shot back, "If you can't handle the hate then stop posting pictures of your girlfriend lol - it should be special between you two only. Don't be mad at your fans. They love you. They were there for you before anyone."

The comment riled her ex, who fired back, prompting Gomez to allege Bieber had cheated on her multiple times when they were together. “I cheated... oh I forgot about You and Zayn?” Justin allegedly wrote in response to her comment, seemingly referencing the former One Direction singer Zayn Malik.

Justin then disappointed millions of his fans by later deleting his Instagram account on Monday (15Aug16).

Now, editors at TMZ.com report a rep for the Sorry hitmaker has claimed Bieber was not behind the comments to Selena on Instagram, blaming bogus accounts instead.

The website alleged on Tuesday (16Aug16) that fake comments posted by trolls were responsible for the offending comments, including Justin's allegation Selena cheated on him with Zayn, and the singer had nothing to do with them.

The 24-year-old Kill Em With Kindness singer later posted an apology on Snapchat after the spat on Monday, writing "What I said was selfish and pointless."

Gomez and Bieber dated on and off from 2012 to 2014.