Charlize Theron - who is dating actor Stuart Townsend - is "bothered" by current "caveman" marriage laws that prevent same-sex couples from getting wed.
Charlize Theron says the current marriage laws are a "form of apartheid".
The South African-born actress - who has previously stated she will not marry her long-term partner Stuart Townsend until same-sex marriage is legal in the US - can't understand why America refuses to give gay people the same rights as their heterosexual counterparts.
She said: "I don't like living in an elitist world, it bothers me. I don't want to be part of an elitist sexual preference. It bothers me, maybe it's because I come from a country where I lived under apartheid but this is a form of apartheid and I don't want to be a part of that.
"It's not the reason I'm not getting married but it's maybe a part of it. My ability to get married is a piece of me that I wish I could give to somebody who it would mean so much to. We should all have the chance. It's just so caveman, I can't believe we're still talking about it."
Charlize, 33, praised 'Milk' - which won Sean Penn a Best Actor Oscar for his portrayal of gay politician Harvey Milk - for helping keep the issue in the public consciousness.
She said: "I just loved the film, I absolutely loved the film. I loved the way it was embraced and the speeches and this conversation that we're constantly having about this issue, I don't want that to go away, I want us to keep having it." | 
