The 45-year-old singer, who was photographed kissing Smart in Los Angeles, has laughed off speculation they are back together, reported E!Online.
When asked about her relationship status, the "Booty" hitmaker said, "I'm single right now, thank you."
The 'American Idol' judge has frequently been spotted with the 27-year-old dancer Casper since they split last summer after three years of dating.
But the choreographer also recently brushed off rumours he had reunited with the actress, who has seven-year-old twins Max and Emme with her ex-husband Marc Anthony.