The "Diamonds" hitmaker and Formula One racing supremo arrived within minutes of each other on August 14 night at The Griffin nightclub, reported Entertainment Weekly.
Rihanna, 27, was spotted getting cosy with Hamilton, 30, at the annual Crop Over carnival in Barbados recently, and the pair spent some quality time together.
"Rihanna and Lewis had a nice little getaway last weekend in Barbados. Rihanna also spent time with her friends and family but Lewis was the only romantic interest on her mind.
"She is taking it very slow and just having fun, but she likes who he is and what he is about. There's no label on them just yet," an onlooker said.
Rihanna was recently linked to superstar Leonardo DiCaprio while Hamilton enjoyed a long-term on-and-off relationship with pop star Nicole Scherzinger.
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