Zoe Saldana claims she's been denied lead roles because of her race.

The 39-year-old star - who has Dominican and Puerto Rican roots - is deemed a ''non-traditional'' casting choice and was always asked to go for ''supporting ethnic'' parts, rather than the main lead.

She recalled of previous auditions: ''Every time I read a script, even if it was a period piece, I read it thinking that I was going to go after the lead role.

''It wasn't until I would come across the introduction of a supporting ethnic role that I realised, 'Oh'. I wasn't even allowed to try to get that main role, because 'They want to go traditional on the part'.

''I would hang up on that conversation from my agents, thinking, 'What about me is non-traditional'? It was a very hard pill to swallow.'

The 'Guardians of the Galaxy' star admitted the restrictions were ''very hurtful'' when she was younger.

She added to PorterEdit magazine: ''In my country, where I pledged allegiance every day since I was five, to be told when I'm out there trying to pursue my American dream that I was not a traditional American was very hurtful.

''I will never accept that I am not a traditional anything. I come from where I come from, I can't change that, and you come from where you come from.''

And the 'Avatar' star - who has three-year-old twins Bowie and Cy and Zen, 15 months, with husband Marco Perego - also claimed she misses out on magazine covers because of her race, but is told it is because her sci-fi roles are deemed too ''masculine'' for women's publications.

She said: ''I feel like the action genre, for many of these editors, feels rather masculine, and I'm just going to say it like that for their benefit, because I've also seen a lot of females that are in action-driven films be on the covers of their magazines.

''I think it has a lot to do with race. 'Colour doesn't sell' - they hide behind that excuse.

''But in reality, if you are in a position of leadership, that means that you have the responsibility to guide the narrative and re-shape it and put it on the right track.''