Tilda Swinton has insisted 'The Room Next Door' is "not really about death at all"

She told Britain's HELLO! Magazine: "I hope people will find it both surprising and nourishing.

"It's about momentous things, possibly the most momentous thing of all, which is, how do we approach our end of live?

"But it's done with such simplicity and lack of drama. That's what one hopes for - to be very graceful about how we live at the end of our life.

"It's not really about death at all. There's very little interesting one can say about death. It's much, much less interesting than living. And this film is all about living."

Having spent time with terminally ill friends in their final days, Tilda found a "sense of catharsis" in making the movie, which also stars Julianne Moore as Martha's pal Ingrid.

She said: "This film, for me, is incredibly personal business and a real blessing of a very profound nature.

"I made no secret of the fact that I've had the privilege over the last few years to be in what I call the 'Ingrid position' quite a lot, and I've been so honoured to accompany several Marthas on their way.

"So to put myself in that Martha position meant that I could put my own experience into the film.

"It gave me the opportunity to put myself in the shoes that I've been sitting beside for quite a long period of my life and I'm regularly sitting beside people in those shoes and learning from them.

"And so what I feel now is a sense of catharsis to actually translate that personal experience into a work of art."

Tilda also plays her character's estranged daughter Michelle in 'The Room Next Door'.

She added: "Personally, I find it tricky when people aren't played by the same person when they're playing their children.

"So yes, I know it's me popping up in a brown wig but my calculation is that it was worth it, and it's less of an obstacle than if it had been an entirely different face."