Rita Ora has revealed she used to date Bruno Mars.

The Hot Right Now singer confessed it was "love at first sight" when she set eyes on the star, before both singers hit the big time.

The Sun reports that Rita told a German mag: "We met in 2009. I was 18 and starting out at Roc Nation. Bruno was unknown back then too.

"He was a struggling songwriter hired to write songs for me. I thought, 'Wow, that's just the world's greatest guy!'"

Rita - who is now dating reality TV star Rob Kardashian - said she and Bruno remained pals after their split.

"Our time together was wonderful. But once we got famous, work got in the way. We ended it last year. But we remained close. And when we were together we were so happy."