Kourtney Kardashian and Justin Bieber enjoy Miami meet up

Kourtney Kardashian and Justin Bieber have once again fueled romance rumors.

The 22-year-old singer and 37-year-old reality star were first linked back in October (15) and have both done their utmost to deny there's anything going on. But the duo caught up once again on Sunday night (03Jul16), when they were both seen at STORY nightclub in Miami, Florida.

Justin was at the nightspot for the official after party following his Purpose world tour gig in the city, and also to mark club owner and restaurateur David Grutman's 36th birthday.

Clearly in a party mood, Justin belted out a birthday song for David, before pulling Kourtney up into the DJ booth with him.

Kourtney, who was in Miami with her three children, was at the club with her pals Larsa Pippen and Jonathan Cheban, and looked incredible for the occasion in a tight leather dress and thigh-high Tom Ford boots.

"Kourtney was there for David's birthday," a source told People. "At first Justin didn't pay any attention to her, but after wishing David a happy birthday he went right down to her table and brought her up to a private table behind the DJ booth."

Justin and Kourtney have been questioned separately about hook up claims ever since their fling was rumored to have begun after they bumped into each other at The Nice Guy in Hollywood last October.

During an interview on radio program The Bert Show, Justin was confronted with headlines surrounding his alleged romance, laughing: "I'm being used, man. What can I say?" When the host asked Justin if there is "anything there?", the Sorry singer replied: "Nah, we'll leave it at that."

But Justin did take the opportunity to praise Kourtney, adding: "No, no, but for real, she's great. I've known (the family) for years."

Meanwhile, it was up to Ellen DeGeneres to quiz Kourtney on the claims when she appeared on her show back in January (16). However, the Keeping Up with the Kardashians star refused to be drawn on the rumors, insisting: "We’re friends."