The Beat Again hitmakers have decided to part ways at the end of the year (13) after a farewell tour, and the four-piece sat down for a chat with Tv host Alan Carr just hours after announcing the news.
The singers were met at the studio by tearful fans, and their reaction prompted Williams to cry during the interview.
He explained, "It's only because I saw the fans literally as we were coming in to see you and just seeing them cry and seeing them upset really evoked that emotion in me.
"But you know, it is a celebration. At the end of the day we've had an amazing six years together. We've been on a journey. Nobody else may have seen the hard times as well as the good times, but we're the luckiest four boys in the world."
The singer was comforted by his bandmate Marvin Humes, and when Williams was asked if he was against the split, he replied, "It is what it is, I guess. The decision was made and we all felt it was the right thing to do."
The full interview airs on Britain's Alan Carr: Chatty Man on Friday (26Apr13).