The friendship between Real Housewives of Atlanta O.G.s NeNe Leakes and Kim Zolciak-Biermann has already been on rocky terms this season. But on Sunday’s all-new episode of the hit Bravo show, any positive feelings the reality stars seemed to be harboring for one another flew out the window as they dove into a bitter battle over Zoclaik-Biermann’s health and the cleanliness of Leakes’ home that quickly became dubbed by fans as #RoachGate.

It all went down in Barcelona, Spain, where Leakes was on vacation with fellow Atlanta Housewives Cynthia Bailey, Kandi Burruss, Porsha Williams, and Shereé Whitfield, as well as RHOA guests Shamea Morton, Eva Marcille, and Marlo Hampton.

Zolciak-Biermann, 39, had skipped the girls trip — a decision she made because husband Kroy Biermann wasn’t invited to come along.

“Less than two years ago, I had a stroke coming from L.A. which is a four-hour flight,” the mother of six explained last week about the mini-stroke she had in September 2015, which led to open-heart surgery after doctors discovered an existing genetic condition that required treatment. “Going to Barcelona, which is a 10-hour flight, does make me nervous. I know that my husband would make sure I’m okay. He knows why signs to look for. …  It makes me very uneasy .”

But just because she wasn’t there didn’t mean that Zolciak-Biermann wasn’t the topic of conversation.

During their ride from the airport, Leakes, 50, slammed the “Tardy for the Party” singer and her close relationship with her football player husband.

“Kim could not join us cause she wanted to come with her husband. This is a girl’s trip,” she said. “The fact that Kim and Kroy have this co-dependency on each other, she can’t do anything unless he’s standing there. What the f—? Like, go do something. Go tackle somebody out on the football field.”

Leakes then shaded the history of health problems Zolciak-Biermann used as reasoning for not wanting to travel alone, implying that was all an excuse.

“Kim is the only person who has had cancer, thyroids, blood clots, open-heart surgery, a stroke, and is still running around here being negative,” Leakes said. “If you’ve had that much, you should be so positive and thankful that God has let you live through every disease in America. Cancer, stroke, thyroid, open-heart surgery, and still living? I can’t get over it. God is good, honey. She’s had it all!”

“The bionic Barbie,” Leakes added. “She’s had every illness in the world!”

RELATED: ‘Close Your Legs to Married Men’: A Brief History of Kim Zolciak-Biermann & NeNe Leakes’ Rocky Friendship

It didn’t take long for Leakes quips to make their way back to Zolciak-Biermann, thanks to Whitfield. “Of course I’m going to talk to Kim and tell her what everybody’s saying,” Whitfield joked to audiences. “A bone carrier is never off her job.”

Her call to Zolciak-Biermann wasn’t met with laughs, though.

“Is this bitch for real?” she told Whitfield, Williams and Morton over the phone. “So you think I lie about having a stroke? I lie about having open-heart surgery? I lie that I take thyroid medicine, bitch? She’s f—— scum and I won’t even acknowledge it. She’s f—— trash. Period.”

“I’m not a cancer survivor,” Zolciak-Biermann also said, clearing up a claim she had first brought up, herself, during the RHOA season one reunion when she pointed to a cancer-scare and “some other problems” as to the reason she wore wigs. “I don’t know who the f— told you that. And nobody f—— said that.”

The Don’t Be Tardy star then went in on Leakes, criticizing her for parking her Rolls-Royce in a handicapped spot during a previous trip to a Georgia mall and for having “roaches” in her house — something her daughter Brielle Biermann had video-tapped during a visit to the property earlier in the season.

She said the same thing hours later, in a text message to the whole group in Barcelona.

“NeNe is sick and disgusting,” she wrote in the lengthy text, which came with video of the so-called “roaches” and a photo of Leakes’ car parked in the handicapped spot. “And I’m not just speaking on the fact that she made fun of a SERIOUS health issue I had… But I am also speaking on the fact that she lives in a f—— roach nest.  For someone who has two beautiful kids and an amazing husband, she should be worried about karma. But this is coming from the same person who takes handicapped spots from the handicapped.”

Her move left Leakes fuming.

“F— Kim, okay?” she shouted. “Can’t none of y’all bitches can step in my house and say a m———— thing because all my s— is brand new with real tags on the bitch, okay? … To say that I live in a roach-infested house? Her and her daughter are disgusting.”

As for the handicapped spot, Leakes assured the group the pass belonged to her husband Gregg, who had recently been hospitalized for heart problems.

“This shows you how much a f—— liar this girl is,” Leakes continued. “She’s a trashy, no-good bitch. She’s always been trash and she’s going to always be trash. That was so calculated and disgusting. … She’s a disgusting, bald-headed bitch.”

Asked if Leakes believed Zolciak-Biermann’s health problems were real, Leakes said no. “I believe she’s an excuse person and I stand by that,” she said.

RELATED VIDEO: Kandi Burruss Reveals That She ‘Never Felt Any Racism’ From Kim Zolciak-Biermann

While viewers will have to wait to see what happens next, fans know that “RoachGate” spilled into social media back in October when Leakes tweeted about Zolciak-Biermann’s text and Brielle’s video — calling the mother-daughter duo “racists.”

“Kim & her daughter oops whole family are racists! What her daughter did at my home, (which she nor kim were invited to so be clear abt that as well) was pure disgusting, racist, learned behavior etc,” Leakes wrote on social media, adding, “children are NOT off limits when you allow your child to talk to adults any kind of way, post disrespectful things on social media and so on. Kim is a calculating bio polar racist with a horrible mouth, who uses black folks for her come up.”

Soon thereafter, Zolciak-Biermann sought out legal counsel, telling E!’s Daily Pop, “I don’t take this lightly. It’s one thing like I said to kind of banter back and forth and have an opinion. This is far beyond just having an opinion.”

The Real Housewives of Atlanta airs Sundays (8 p.m. ET) on Bravo.