Lopez, 42, began dating back-up dancer Smart, 25, following her split from husband Marc Anthony last year, reported People magazine.
Lopez tried not to talk about the rumours that they were set to marry when she was wearing a band on the finger.
In a post titled 'The Truth About The Ring', on her website, she wrote, "Is there a ring on my finger? Let me tell you, rumours!!! Don't be fooled by the rocks that I got. No engagement."
