They may have played best friends on the big screen, but Sarah Jessica Parker and Kim Cattrall's real-life relationship is far from amicable.

The two Sex and the City actresses have been publicly feuding for several months now, exchanging jabs on social media, but in the wake of her brother's tragic death, 61-year-old Cattrall made a definitive statement about her relationship with Parker: "You are not my family. You are not my friend."

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According to the New York Post, the rift between Parker and Cattrall, who played Sex and the City's Carrie and Samantha, respectively, started on the set of the hit TV show, where the leading actresses allegedly formed a "clique," purposefully excluding Cattrall. The source reports Parker rented a house for herself, Kristin Davis, and Cynthia Nixon, and that, by the end of filming, the three actresses refused to speak to Cattrall.

Despite these alleged tensions, the four women filmed two Sex and the City movies, and there were even rumors of a third film, which had a script and everything, Parker told Extra. But reports surfaced that Cattrall's demands led to the project being cancelled, and that's when her feud with SJP was seemingly reignited, culminating in a barbed Instagram post this weekend.

The most recent exchange between the on-screen soul sisters is heated, to say the least. Following news of Cattrall's brother's passing, Parker commented on Cattrall's Instagram, writing, "Dearest Kim, my love and condolences to you and yours and Godspeed to your beloved brother."

Cattrall made it clear she doesn't want Parker's sympathy, however, responding with a scathing statement on Instagram. The post itself reads, "I don't need your love or support at this tragic time @sarahjessicaparker," and in the caption, Cattrall expands her rant, calling her former costar a hypocrite and accusing her of exploiting the tragedy to boost her own image.

Parker has shared several social media posts following Cattrall's outburst, but none in direct response to it. On Valentine's Day, she offered a sweet and neutral message for everyone, writing, "I hope everyone feels some love today."