Cynthia Nixon says she "chose" to be gay.

The former 'Sex and the City' star is engaged to her long-term partner Christine Marinoni -- with whom she has an 11-month-old son Max -- and despite angering many people, she insists it was aa decision to become a lesbian.

Cynthia -- who was with former partner Danny Mozes for 15 years and had two children, Samantha, 15, and nine-year-old Charlie, with him - said: "I gave a speech recently, an empowerment speech to a gay audience, and it included the line 'I've been straight and I've been gay, and gay is better.'

"And they tried to get me to change it, because they said it implies that homosexuality can be a choice. And for me, it is a choice. I understand that for many people it's not, but for me it's a choice, and you don't get to define my gayness for me. A certain section of our community is very concerned that it not be seen as a choice, because if it's a choice, then we could opt out.

"I say it doesn't matter if we flew here or we swam here, it matters that we are here and we are one group and let us stop trying to make a litmus test for who is considered gay and who is not."

Cynthia, 45, insists she hasn't always been gay and finds it "offensive" that people say she has.

She told The New York Times: "Why can't it be a choice? Why is that any less legitimate? It seems we're just ceding this point to bigots who are demanding it, and I don't think that they should define the terms of the debate.

"I also feel like people think I was walking around in a cloud and didn't realise I was gay, which I find really offensive. I find it offensive to me, but I also find it offensive to all the men I've been out with."