Justin Timberlake and Anna Kendrick perform Trolls duet in Cannes

Justin Timberlake and Anna Kendrick performed a sweet duet from their new movie Trolls for an audience at the Cannes Film Festival.

The pair took to the stage at the city's iconic Palais des Festivals et des Congrès venue on Wednesday (11May16) to sing a cover version of Cyndi Lauper's 1986 hit True Colors. At the mini-gig on the French Riviera Justin played acoustic guitar and Anna, who began her acting career in musical theatre, joined him on vocals for an emotional rendition of the song from the movie's soundtrack.

The crowd at the Palais also saw footage from the Dreamworks animation, which is due for release this autumn (16).

In the new film, which features animated versions of the popular Troll doll toys, Anna plays a troll character called Princess Poppy who goes on an adventure with another of her kind, Branch, played by Justin.

According to the Cry Me A River musician as well as singing True Colors with Anna for the film's soundtrack, castmate Jeffrey Tambor asked him to provide original music for the film.

Justin tells U.K. radio show Capital Breakfast with Dave Berry, George and Lilah, "When I was first brought in as the lead opposite Anna (Kendrick) in Trolls, Jeffrey (Tambor) pulled me aside and said, 'I want you to do all the music. Apart from some existing music we’re using for comedic purposes with some covers.'

"So he pulled me in and said "I want you to be Executive Music Producer" or some silly title. My first reaction was, wow really cool and then on the drive home I was like, this seems like a lot of work."

Justin's first single in three years, Can’t Stop the Feeling was also written for the film and was released last Friday (06May16). He will perform the track at the final of the Eurovision song contest, in Stockholm, Sweden on Saturday (14May16).

Trolls is scheduled for release on 4 November (16).