Members of NSync, from left, Lance Bass, Joey Fatone, Justin Timberlake, JC Chasez and Chris Kirkpartrick perform at the 9th annual MTV Movie Awards in Culver City, Calif. Picture: AP

NSYNC have revealed their so-called feud with Backstreet Boys boiled down to a girl.

Chris Kirkpatrick of the 'Dirty Pop' boy band - also comprised of Justin Timberlake, Joey Fatone, Lance Bass and JC Chasez - has revealed he locked heads with AJ. McLean after the 'Larger Than Life' hitmaker started seeing an ex-girlfriend he'd recently broke up with, and he was so furious he wanted to "kick his a**".

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Chris recalled: "I wanted to punch AJ [McLean's] lights out for a little while. I was dating a girl, I broke up with her and he started dating her.

"And I guess he was talking smack to her about me, so I confronted him on it and wanted to kick his a**."

However, the pair soon patched things up and went out for drinks together.

He said: "I don't know how it got resolved -- I saw him out one night and said I wanted to kill him, but I said, 'Let's get a beer."

Joey insists that it was not a proper feud with their rivals - completed by Nick Carter, Kevin Richardson, Brian Littrell and Howie Dorough - and was simply "friendly competition".

He said: "It created a friendly competition. There's nothing wrong with friendly competition -- even though we are, of course, better than any of those boy bands. Maybe not right now, a little rusty."

Chris confessed: "I think boy band fights are in the same realm as hockey fights. You fight when you're on TV, but then when you're not, you get a beer together. Now we're really good friends."

And JC added: "We can't control how people are gonna take it. "All we can do is control how we give it."

Backstreets Boys beat NSYNC to a star on the Hollywood Walk of Fame by receiving the honour in 2013, however, it was recently announced that the 'It's Gonna Be Me' hitmakers will get their star on April 30.