RiRi is relaxing onboard a yacht on the French Riviera, and has been snapped in a string of skimpy bikinis as she unwinds on her hols.
She has also been joined by friends on the trip - and when Chris flew into the country, it prompted speculation he was there to see his ex.
The Sun even reported the former couple - who split after a highly-publicised 2009 bust-up - had spent a romantic evening together.
But Chris's rep has brushed off the gossip and revealed he is on a work trip and being accompanied by his current girlfriend, model Karrueche Tran.
The spokesperson tells US website HollyScoop.com: "CB (Chris Brown) is in France to shoot a music video for Swizz Beatz album (sic) and Ludacris is in it. It's Swizz's song. Karrueche is there with him... They never broke up.
"He is not on her [Rihanna's] yacht. There is no Rihanna connection."
It is the second time in little over a month that the ex-couple has been linked - it was alleged that they shared a hotel room in New York City on 11 June.
Brown's rep shot down that gossip, insisting the singer is madly in love with Karrueche and would never do such a thing.