The 'Baby' hitmaker hit back at the 'Bad Neighbours' actor - who previously branded him ''obnoxious,'' ''ungrateful,'' and ''insincere'' - after Seth recalled the first time they met during an interview on 'The Howard Stern Show', where he called the singer a ''motherf***er'' who acted like he was the one who had requested to meet the teenage star.
Justin defended his behaviour putting it down to being a ''bit shy'' and insists he still likes the comedian's work.
He wrote on Twitter: ''Seth Rogan sorry I didnt bow down when I asked 2 meet u was probably a bit shy and didn't want to be over the top but still. love ur movies (sic)''
Hours earlier, Seth insisted it's easy to ''hate'' the 20-year-old star because he lives up to the bad reputation which he's gained in recent months.
Seth explained: ''He's a good example of someone you meet, who you think you're going to hate, and then you get to hate him as much as you thought.
''You meet him, and he lives up to every one of your expectations of how you hope he will be.''
Seth previously lashed out at Justin after he was charged with drink driving, resisting arrest and drag racing in Miami, Florida in January.
The 31-year-old comedian and actor tweeted: ''All jokes aside, Justin Bieber is a piece of s**t.''
The post was shared by more than 70,000 other users within four hours.
Spencer Morrill believed he was in a relationship with the singer and that she was hiding messages for him in her songs.
Was the singer unknowingly taking counterfeit pain medication?
Roberts had left the band in 2012, due to problems with blood circulation and other health issues.
The popstar turned actress is back in the studio.
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