"I am so sorry for what has happened @neneleakes," Zolciak wrote.
"We both know the truth, we both know that if I wanted to, I could have a law suit for the lies you have spewed, tweeting out fake texts, implying I am racist, attacking me physically, claiming my daughter tweeted negative about you and your home, we both know these are lies."
"I have reacted to it publicly and for that I am sorry. I should have risen above it," she added. "I personally will no longer engage with you on social media and perpetuate the hate. I am asking you to do the same. We are grown women with families. Enough is enough."
"I want us to move on," the star said. "If you continue this, it will be because you are attempting to stay on the show and stay relevant and that's on you."
Zolciak and Leakes have been feuding since Zolciak's daughter Brielle Biermann posted a video in October of alleged cockroaches in Leakes' home.
Zolciak denied she's racist in March after Leakes suggested as much on Real Housewives.
"The video was made in good jest," Zolciak said on Watch What Happens Live.
"I'm definitely not racist," she added. "I don't associate roach -- whatever, spider, whatever -- [with race] in my mind."
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