The 'Where Have You Been' singer was named the new face of the Armani underwear print and video campaign last summer, and appears semi-nude in the black & white editorial.
Reports emerged earlier claiming that the bottom in the video actually belongs to Irish model Jahnassa Aicken, who allegedly signed an agreement with Rihanna's management saying that she would not reveal her involvement.
However, the pop singer slammed the report via her Twitter account, insisting that a tattoo on her hand in the video proves that it is her.
Rihanna wrote: "Ok @thesunnewspaper, this is the only way I could say this to you!!! F**K YOU… Who is Jahnassa… Does she have a tat (tattoo) on her hand too?"
The Bajan songstress recently also blasted claims from the media that she is suffering from an emotional breakdown, calling the reports "bull***t".
Watch the Armani ad below: