Alicia Keys has revealed she is pregnant with her second child.

The Grammy-winning singer announced the news on social networking sites as she celebrated her fifth wedding anniversary with her producer husband Swizz Beatz, aka Kasseem Dean.

She posted on Instagram a photo of the couple cradling her baby bump and wrote: "Happy Anniversary to the love of my life @therealswizzz !! And to make it even sweeter we've been blessed with another angel on the way!!

"You make me happier than I have ever known! Here's to many many more years of the best parts of life!" she added.

Swizz also shared an image from the same shoot with the caption: "Love is life & life is love and we're so excited for another GIFT from up above. Happy Anniversary my Goddess 4 years of greatness & cheers to 100 plus more inshallah."

Alicia previously hinted that she wanted to add to their family, when she told E! News last November: "Not right now, but never say never!"

The couple, who married in 2010, are already parents to three-year-old son Egypt Daoud. Swizz also has three children from previous relationships.