Cynthia Nixon is planning to marry her lesbian lover Christine Marinoni, it has been claimed.

The 'Sex and the City' star - who reprises her role as lawyer Miranda Hobbes in the upcoming movie adaptation of the hit TV show - reportedly wants to tie the knot with education activist Christine to show her how much she appreciated her support while she was battling breast cancer.

A source close to the 42-year-old actress told the National Enquirer magazine: "Cynthia and Chris want a quiet autumn ceremony in Vermont under the red leaves. It's supposed to be a very low-key gathering just for close friends and family."

Cynthia - who was diagnosed with the disease after a routine mammogram 18 months ago - told friends Christine was her "rock" while she was undergoing radiation therapy for to treat the cancer.

The couple first met seven months after Cynthia left her partner of 15 years, Danny Mozes, who is also the father of her children - 11-year-old Samantha and five-year-old Charles.