Lenny Kravitz is refusing to confirm or deny he's the man who was secretly engaged to Nicole Kidman between her marriages to Tom Cruise and Keith Urban. The actress recently stunned fans when she revealed she had briefly accepted a marriage proposal before she wed Urban last year (06) in Vanity Fair magazine - but she refused to name names. Kravitz and film producer Steve Bing were the most likely candidates as Kidman dated them exclusively after her marriage to Cruise ended. But Kravitz insists the identity of the mystery fiance will remain a secret, as far as he's concerned. He says, "I keep that to myself. I feel like that is private and it's between the two of us, so I just leave it there."