'It could have been one of the most incredible records ever,' he says of his attempt to record with Winehouse.

"We met and we talked about it for a moment when I saw her," Usher said of a brief sit-down with the troubled crooner to discuss the potential soul summit.

"There was a few conversations that took place, but we never quite made it to it ... I would have loved it." One of those talks occurred while the unlikely duo were shopping at the ritzy London department store Selfridges. "I was shopping and she was doing some private shopping and she came out and we kind of crossed each other's [paths] and, [I was like] 'Is that Amy Winehouse?' ... And before you know it we talked and exchanged information and I invited her to a show ... and she didn't come."