Almost a week after confirming her missing brother had been found dead, Sex and the City actress Kim Cattrall hit out at her former co-star Sarah Jessica Parker.

“I don’t need your love or support at this tragic time,” she wrote on Sunday, adding that her co-star’s “continuous reaching out” served as a “painful reminder of how cruel you really were then and now”.

“Let me make this VERY clear. (If I haven’t already) You are not my family. You are not my friend,” she wrote.

“So I’m writing to tell you one last time to stop exploiting our tragedy in order to restore your ‘nice girl’ persona.”

My Mom asked me today “When will that @sarahjessicaparker, that hypocrite, leave you alone?” Your continuous reaching out is a painful reminder of how cruel you really were then and now. Let me make this VERY clear. (If I haven’t already) You are not my family. You are not my friend. So I’m writing to tell you one last time to stop exploiting our tragedy in order to restore your ‘nice girl’ persona. Copy and paste link https://nypost.com/2017/10/07/inside-the-mean-girls-culture-that-destroyed-sex-and-the-city/

A post shared by Kim Cattrall (@kimcattrall) on Feb 10, 2018 at 5:20am PST

While many became aware of the feud between Parker, 52, and Cattrall, 61, after it was revealed a third Sex and the City would not be going ahead late last year, the bitterness between the two actresses has been going on for years.

In fact, it started almost as soon as the HBO show began filming in 1998.

The rivalry between the two is documented in a New York Post story, a link to which Cattrall provided in her Instagram take-down of Parker.

The article, titled Inside the mean-girls culture that destroyed 'Sex and the City', claims that Parker deliberately excluded Cattrall from the very beginning, jealous of her "scene-stealing" talent and her status as a bigger star at the time.

A book proposal submitted by Clifford Streit, who was the real-life inspiration for character Stanford Blatch, said tensions began when Parker realised Cattrall was a "natural comedienne".

LISTEN: The Sex And The City franchise has reached its demise. Post continues after audio...

Parker - the show's lead and heroine - then formed a "clique", consisting of co-star Cynthia Nixon, who she knew from her days on Broadway, and Kristin Davis. Cattrall was deliberately left out of group activities, and during filming in New Jersey, was purposefully not invited to stay in a house that Parker had booked for her fellow co-stars.

"Sarah Jessica rented a house for herself, Kristin Davis and Cynthia Nixon. Kim Cattrall was left out on her own," Page Six reported, although HBO representatives maintained that Cattrall had requested her own accommodation as she was married at the time and preferred to stay with her husband.

By the end of the show's filming, six years in, the New York Post reports Parker's reign on set as 'Queen Bee' was so strong "no one would talk to Kim... not even in the makeup room."

After being excluded for so many years, Cattrall was reluctant to sign on for the first Sex and the City film. Despite the fact it was a critical success, making more than US$415 million worldwide, when negotiations rolled around for the film's sequel, Cattrall was blasted publicly for her "diva demands".

"There was a disparity between what Sarah got and what the other girls got," a friend of the actress told The New York Post.

"Everyone loved Kim's character, people related to her — and [Kim's] salary wasn't showing that."

The same narrative was repeated last October, when Sarah Jessica Parker revealed a planned third movie would not be going ahead.

"I'm disappointed. We had this beautiful, funny, heartbreaking, joyful, very relatable script and story," she told E! News.

"It's not just disappointing that we don't get to tell the story and have that experience, but more so for that audience that has been so vocal in wanting another movie."

Cattrall's 'diva demands' were again blamed for the movie's downfall, but this time, the actress - now aged 61 - was fighting back.

Woke 2 a @MailOnline ????storm! The only 'DEMAND' I ever made was that I didn't want to do a 3rd film....& that was back in 2016

— Kim Cattrall (@KimCattrall) September 29, 2017

Cattrall then booked an interview with talk-show host Piers Morgan, reiterating that her answer to a third film had always been, and would continue to be, 'no'.

"I never asked for any money, I never asked for any projects," she said.

"To be thought of as some kind of diva is ridiculous."

She also opened up on the 'mean girls' culture on the SATC set, describing it as like a "toxic relationship".

"Sarah Jessica, she could have been nicer, she could have in some way. I don't know what her issue is, I never have."

By the looks of Cattrall's most recent Instagram post, it seems this is a relationship well beyond repair.

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