She may be rehearsing for one of the biggest performances of her career, but it seems that Katy Perry doesn't need to drink alcohol to calm her nerves.

The 26-year-old pop star touched down in Rio de Janeiro yesterday ahead of her appearance at the Rock N' Rio Music Festival and, after rehearsing, headed out to dinner with a group of friends.

The I kissed a Girl singer wore a butterfly print maxi dress with halterneck straps and purple jewelled sandles for her night out at the Porcao restaurant in Brazil.

Still sporting her blonde and pink locks, the star also wore a butterfly in her hair and a pair of gold chandelier earrings.

After laughing with friends over dinner, Katy left the restaurant and happily posed for photographs with waiting fans before making her way to a waiting car.

The star was probably shattered after her flight, and day of rehearsals.

The legendary festival in Rio de Janeiro, which is the biggest in the world, often has an attendance rate in the hundreds of thousands so Katy obviously wants to nail her performance.

The star paid tribute to another singer, Portuguese Brazilian-born Carmen Miranda, by arriving at the airport wearing a mask that resembled the famous samba singer - who was famous for wearing a fruit hat on her head.