Rihanna has learnt to be "fearless" in order to survive the entertainment industry.

The 24-year-old star admits she was nave when she first started out as a singer. However, she has since matured and is now confident to trust her own instincts.

"It's really easy for me to zone out, get in my own world. I need to be really stern about the point I'm trying to make, even if not verbal," she told British magazine We Love Pop. "You need to be fearless."

Rihanna can soon be seen making her movie debut in Battleship. Her inner strength also proved vital on the set of the action film.

"You need to be unaffected in the movie industry," she explained. "In the music industry too, because there is so much scrutiny and negativity. You need thick skin. I grew a set of balls that are very big. Ha ha!"

Rihanna plays Petty Officer Raikes, who is a weapons specialist, in Battleship.

The movie also stars Liam Neeson and Alexander Skarsgrd.