Actor Seth Rogen had some choice words when asked about the recent behaviour of Justin Bieber.

The 'This Is The End' actor branded the troubled 20 year-old as "obnoxious" when being interviewed on Andy Cohen's 'Watch What Happens Live' with Dave Franco.

Rogen was asked to elaborate on a controversial tweet he posted back in January that stated Bieber was a "piece of s**t."

And his feelings haven't change at all.

When speaking to Cohen on a special addition of his show at the South by Southwest festival, Seth said, "In my opinion, Justin Bieber is a piece of s**t."

"He seems like he's obnoxious and ungrateful, insincere, and he puts people's lives at danger and overall he acts like a piece of s**t," he ranted.

The 31 year-old first showed a dislike towards Bieber when the 'Boyfriend' singer was arrested for driving under the influence (DUI) in Miami while drag racing, this past January.

Seth tweeted, "All jokes aside, Justin Bieber is a piece of s**t, and this has been retweeted over 200,000 times since.

On a lighter note, Rogen also spoke to Cohen about his shirtless parody of Kanye West's awkward 'Bound 2' music video, which featured Kim Kardashian. But what is surprising, is that the high-profile couple found the clip, which featured James Franco, hilarious.

The 'Green Hornet' actor said, "I've seen both Kim and Kanye since that video came out, actually. And they both think it's really funny, thank God!"

"I was worried because I'm a big Kanye West fan, like a huge Kanye West fan. I saw him in New York," he continued. "And he pointed to my wife, like 'How come she wasn't on the motorcycle?' But he was pleased and humoured by the experience."

Seth Rogen
Seth Rogen is not a Justin Bieber