Lulu might be asked to join Take That on tour to sing her guest vocals on Relight My Fire, Howard Donald has said.
The band will be touring together for the first time in 16 years next year, and Howard said he would suggest bringing Lulu back for part of the tour.
"We might ask her, there's every possibility - I'll put that one forward to the lads," he said.
Howard added that having Robbie Williams back on tour with them would make the shows more exciting.
The singer said: "It's going to bring surprises, because Robbie's got his own mind and can go off on an tangent. He's an amazing performer whereas I do what I do, I do my songs, I perform but I've never been the sort of showman like Robbie."
Take That's tour with Robbie, which coincides with their reunion album Progress, has been a year in the making, Howard said, and he promised they would try to top their Circus tour.
He said: "The Circus cries out for so many different things for a show whereas Progress doesn't, but there is meaning behind Progress and there is a way of transferring that on to the stage."