Gillian Anderson suffers panic attacks when on the stage.

The 'X Files' actress - who has previously appeared in 'The Vagina Monologues' and 'A Doll's House' in London's West End - is keen to return to the theatre but finds the experience terrifying.

She said: "I'm constantly thinking about doing more theatre, particularly when I see a good play.

"I have a couple of ideas but I like to wait two years between parts because that's all I can handle.

"I have to park my fear. I find it absolutely terrifying, have panic attacks and wonder why the hell I'm doing it. It's almost as if you're never left off the hook: panic lingers over my shoulder."

Despite her fears, the 42-year-old actress is happy to do it because she thinks is no better feeling when the job is done well.

She said: "There's nothing like it. I can walk on a stage and I feel so emotional I start crying.

"I don't know why. It's not ego. It feels like the antithesis. Ego is squashed all the time. But I've ever been worried what people think of me. Well, I don't think I have."