"As an actress I feel that playing Gemma will be one of the most important opportunities of my life," Cruz told the daily La Repubblica.

The Spanish actress will once again work with actor-director Castellitto to star in "Venuto al Mondo" (Into the World), which tells the story of a mother who accompanies her teenaged son to present-day Sarajevo, where the boy's father died during the World War II.

The Oscar-winning actress earlier worked in Castellitto's film "Non Ti Muovere" (Don't Move) in 2004.

"Venuto al Mondo" is based on Mazzantini's latest book of the same title, which has sold more than 300,000 copies in Italy since its publication in 2009.

"It's a book that makes you feel and even smell the war. I don't usually like war stories, because the violence never seems that real to me, but in this story it hurts you. It makes you feel all fear and desperation of actually being there," Cruz said.

The actress said that, after finishing her shooting for the sequel of the "Pirates of the Caribbean", she is going to take a "long break to get ready for playing the part of Gemma".