AceShowbiz - Rihanna already has her wedding dress design in mind after confessing she's in a committed relationship with a mystery man, believed to be Saudi businessman Hassan Jameel.

The "Diamonds" singer tells the new issue of Vogue she's dating and has been "in an exclusive relationship for quite some time," prompting magazine editor-in-chief Anna Wintour to press her about marriage and children in an accompanying video.

In the "Go Ask Anna" promo, Rihanna reveals she'd love to be a mum one day, before adding, "I don't think about stuff like that, but God's plan, but I look forward to all of the pregnancy rumors after this interview."

But she does think about her wedding day - and what she'll wear for her vows: "A collaboration between myself and (John) Galliano, of course," she tells Wintour.

Rihanna and Hassan, who have been linked romantically since 2017, have been spotted on several dates, including a recent night out at Santa Monica, California steakhouse Mason.

Her "Ocean's 8" co-star Sarah Paulson also asked Rihanna about her marriage plans during a chat for Interview magazine in June, and the singer responded, "Only God knows that, girl. We plan and God laughs, right?"