Ariana Grande covers one of her "favourite songs of all time"

Ariana Grande treated fans at a recent concert to an unexpected cover and special guest performance.

The 21 year old music star is currently on her Honeymoon world tour and decided to make a new addition to the set list when playing in Inglewood, California earlier this week.

Seated upon a piano whilst wearing a white dress and glittery high heels, Grande told the crowd that she was nervous but excited to be performing with “one of the most incredible songwriters of all time” and that they would be covering one of her “favourite songs of all time”.

Ariana laughed: “It was my go-to song to sing at a gay bar, at a karaoke bar, anywhere!”

The ‘Problem’ star welcomed songwriter David Foster to the stage to play the piano whilst she sang Whitney Houston’s ‘I Have Nothing’ (see video below).

‘I Have Nothing’ is taken from the soundtrack to the 1992 film ‘The Bodyguard’ starring Whitney Houston and Kevin Costner.

Ariana Grande recently announced more North American tour dates that will take place from July through to October.

Watch Ariana Grande covering Whitney Houston below: