The 38-year-old singer announced his engagement to Nazarov on his Twitter page, adding that he's "the happiest man alive!!"
He also posted a photo of a Neil Lane ring, which he gave to his fiancée.
"Great news - I'm getting married to Esther [Nazarov] in July!!!!" People quoted him as writing on Twitter.com.
"It's on!! Break out the bubbley!!"
"I've never known true love until now. So grateful," he added. (ANI)