Kathy Griffin is firmly Team Kelly Clarkson.

The outspoken comedian defended the “American Idol” winner amid her bitter feud with a Brooklyn toy store, blasting the business as “petty” for how it handled the controversy.

“I’m Team Kelly because I just love her,” Griffin, 65, told Page Six in an exclusive interview. “I’ve known her since the night she won ‘American Idol,’ and I think she has become more real since her [talk show] got canceled, more herself.”

A feud erupted over the weekend when Clarkson, 44, slammed Art of Play on social media, accusing an employee of treating her poorly after allegedly assuming she couldn’t afford a rare mechanical singing bird named Molly, which had a price tag of $15,000. (The price tag now reads $15 million.)

The former talk show host claimed that the staffer was patronizing and rudely offered to find her a cheaper alternative, prompting her to call him an “idiot” who had forfeited a “huge sale.”

Clarkson said she felt treated like Julia Roberts’ character in “Pretty Woman” when Vivian Ward is treated badly by snooty staff on Rodeo Drive.

Griffin believes that Clarkson is telling the truth.

“I know her well enough to know she is not somebody who would hop online, make up a lie that would be so outrageous it could take down a business,” Griffin explained. “She is well aware of the size of her fan base…I think Kelly probably made the post without a ton of thought. I doubt she got together with her pr and legal team. She was probably like me, posting late at night, and I believe her because she doubled down.”

Clarkson doubled down after the store offered a tepid apology and accused them of lying about the situation.

The “My Life on the D-List” star stressed that she’s not a “corporate shill” and understands Art of Play is an independently owned business, but thinks they missed the ball.

“I actually think they look petty and the store would blow up, business-wise, if they had just said, ‘Oh my god, we’re so embarrassed,'” she opined. “I think the store could have said, ‘We all have bad days at the office, and I think whoever she was dealing with personally should have sent her flowers and said, ‘I was having a bad day.'”

One of the store’s co-owners, Adam Rubin, has hit back at Clarkson and her “reprehensible abuse of power,” which unleashed a torrent of online abuse against the business.

“It’s a pop star, a mechanical bird; it’s surreal. When this thing first started, everybody wanted us to die,” Rubin exclusively told Page Six, referring to the hundreds of threatening messages his staffers have received since Clarkson dragged their store on social media.

“And as the truth has come to light, thinking people realize this is reprehensible abuse of power,” he continued. “We have to reconsider the place we give celebrities in our society.”

Griffin is currently on tour and will be performing at The Town Hall on Friday.