The British band will be taking to the Pyramid Stage at the famous U.K. music festival on 26 June (16). It was reported earlier this year (16) that 69-year-old Barry would join them as their special guest, but the illness of a family member has apparently caused him to pull out.
"Barry has had to stay put in Florida as a close family member is unwell and he needs to be with them. It’ll be a shock if he makes it," a source told Britain's The Sun newspaper. "He is disappointed as he was really looking forward to playing at Glastonbury.
"He’s a good friend of (frontman) Chris (Martin) and the band and didn’t want to let them down, but there is just no time for him to get to England to rehearse."
Now Coldplay are said to be rushing to rustle up another musical guest for their set. And with Adele and Ellie Goulding among the other superstars on the bill for the event, they have a selection to choose from.
"Coldplay had planned a big, colourful set around Barry’s appearance," the source added. "The medley was going to be in the middle of it all as a centrepiece. Now they are having to go back to the drawing board and think up a different surprise, which isn’t what they need when they’re doing a world tour.
"But if there is anyone you can rely on to come up with something special, it’s Coldplay."
Coldplay have also allegedly made the decision to use their Glastonbury set to pay tribute to indie band Viola Beach, who died along with their manager in a car crash in Sweden in February (16).
According to reports, the group will cover one of Viola Beach's songs during their set.