Has Bethenny Frankel taken her feud with Ramona Singer to the next level by befriending her former husband's mistress, Kasey Dexter?

According to a new report, Frankel and Singer are at war during the ninth season of The Real Housewives of New York and they are experiencing off-screen drama as well.

On Friday, Radar Online revealed that Frankel crashed at one of her friend's homes in the Hamptons before buying her own place and during her stay, she reportedly made friends with Dexter, who was staying at the same home.

“Kasey [Dexter] and Mario met at their friend’s home in the Hamptons in 2013,” an insider told the outlet. “She had a bruise on her butt from getting hit with a tennis ball and he came up to her and was flirting with her, talking about the injury. Ramona was right there and witnessed the whole thing. Mario asked for her number and the next day she sent him pictures. They were on their friend’s yacht and Mario almost had a heart attack!”

“Bethenny was staying at the same house as Kasey that summer,” the insider added. “They used to be friends... Bethenny knew everything that was going on! Maybe that’s why Bethenny and Ramona deep down don’t like each other!”

As fans may recall, Singer filed for divorce after she caught her now-ex-husband Mario Singer at their Hamptons home with Kasey Dexter.

To see more of Ramona Singer, Bethenny Frankel, and their co-stars, including Sonja Morgan, LuAnn de Lesseps, Dorinda Medley and Tinsley Mortimer, tune into the ninth season of The Real Housewives of New York on Wednesday nights at 9 PM on Bravo TV.