Christine Marinoni and Cynthia Nixon

Sex and the City star Cynthia Nixon plans to marry her girlfriend — in the city.

Nixon announced her engagement to girlfriend Christine Marinoni in New York City at a weekend rally for same-sex marriage, Access Hollywood reports.

The actress told the crowd, which included Sex co-star Kristin Davis, David Hyde Pierce, Audra McDonald and Ana Ortiz, that the couple got engaged last month. Nixon and Marinoni support a bill by New York Gov. David Paterson that would allow same-sex couples to marry.

Nixon, who will start shooting the Sex sequel this summer, started dating Marinoni in 2003, shortly after her split from boyfriend Danny Mozes. She and Mozes have two children, Samantha, 14, and Charles, 6.

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