Seth Rogen joins Bieber bashers, calls him ‘ungrateful, obnoxious’

Seth Rogen has thrown in his lot with the Bieber bashers.

The “Neighbors� star, 31, stopped by Andy Cohen’s “Watch What Happens Live� on Wednesday, and the host asked him about a tweet he’d posted in January following Justin Bieber’s arrest on suspicion of DUI in Miami.

Sorry, guys, we can’t republish the tweet here, but it involved Rogen calling the pop star “a piece of� something.

The 20-year-old “Beauty and a Beat� singer’s latest antics have further sullied his name. Those jail photos and videos and that notoriously unflattering deposition video haven’t done much to help his case, especially given that they came after vandalism allegations and accusations that Bieber had been speeding through residential streets.

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Anyway, when Cohen brought up Rogen’s tweet, the actor piled it on.

“In my opinion, Justin Bieber is a piece of ...,� he said again. “He’s obnoxious and ungrateful and unsincere and he puts people’s lives in danger.�

Oh, tell us how you really feel, Seth.

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The notorious Hollywood stoner, who recently testified before Congress about Alzheimer’s disease, also “spilled the herbal tea� on the show by sharing the names of a handful of celebrities with whom he’s smoked weed. They include his “Knocked Up� costar Paul Rudd, comedian Sarah Silverman and rapper Snoop Dogg. Rogen said he only talked about it with his “Guilt Trip� costar Barbra Streisand, but she said she happened to smoke with legendary actor Peter Sellers (“The Pink Panther,� “Dr. Strangelove�).

Late last year, Rogen and his “This Is the End� costar James Franco spoofed Kanye West’s “Bound 2� music video, which featured West’s fiancée Kim Kardashian inexplicably riding topless backward straddling the singer on a motorcycle. The pair called their version “Bound 3� and got positive feedback from the usually combative rapper.

“He was pleased and humored by the experience ... as he should have been,� Rogen said. “He’s a sweetheart and a mensch.�

#uhhuhhoney

Rogen’s “Neighbors� costar, Dave Franco (yes, James Franco’s younger brother), appeared on the Bravo talk show with Rogen and revealed that he’d tested for the role of vampire Edward Cullen in “Twilight.� That, of course, prompted a giddy Cohen to ask them to re-enact the sunlight scene from the first film in the mega-popular franchise. Rogen donned a brunet wig to dramatically play Kristen Stewart’s Bella Swan, and Franco played Robert Pattinson’s Edward. It’s hilarious: Watch it here.

“Neighbors� knocks its way into theaters May 9.

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