Seth Rogen is not exactly a fan of Justin Bieber. In fact the Bad Neighbours star has been very upfront about his dislike for the pop star.

So Justin seems to be asking for trouble, as he REALLY wants his fellow Canadian to be a part of his Comedy Central Roast, which is being recorded later this month.

Justin Bieber (Zacharie Scheurer/AP)
Justin Bieber (Zacharie Scheurer/AP)

Justin, who turned 21 on March 1, has been pestering Seth on Twitter to give him a good roasting.

He even got his 61 million followers to try and persuade the Knocked Up star with the hashtag #WeWantSeth.

Seth’s beef with Justin kicked off a year ago when the actor tweeted: “All jokes aside, Justin Bieber is a piece of s***.”

The Interview star also signed the petition to have the Baby singer deported from the US following his string of bad behaviour, which included him admitting to careless driving and resisting arrest and being ordered attend anger management classes after throwing eggs at his neighbour’s house.

Seth later revealed to shock jock Howard Stern that his problem with Bieber had begun when the singer asked to meet him, and then when Seth went to greet him, acted like he didn’t care.

Justin Bieber with a live snake at the MTV awards (FRANCIS SPECKER/LANDOV)
Justin Bieber with a live snake at the MTV awards (Francis Specker/Landov)

The This Is The End star said: “I met him a few times. He’s a good example of someone, who you meet, who you think you are going to hate and then you get to hate him … you meet him and he lives up to every one of your expectations.

“I saw him again at like an MTV awards show, he literally had a snake wrapped around his f***ing wrist that he was wearing.

“I talked to him for like five minutes … No humility, no awareness, no sense that ‘I appeal to young, young people, maybe a grown man who works in comedy doesn’t f***ing give a s*** about me. Maybe I should act in such a way that perhaps this isn’t the great experience of his f***ing life’.”