Pop superstar Robbie Williams will join his former band Take That for a one-off performance on their comeback tour. The group, who have reformed for the British trek which kicks off later this month (APR06), had previously told fans that Williams would not be taking part. An insider tells British newspaper The Sun, "Robbie has agreed to appear at one of the Take That gigs in Manchester. They are working out schedules and haven't yet decided which of the dates it will be. "But it is a done deal. Everyone involved has been sworn to secrecy. "Robbie will be there to sing one number. They are working out all the details now."