One of Britain's reigning musical giants will be on hand to see England's future king and queen get hitched.
"We do have an invitation," John told Canada's CTV. "I've been trying to be discreet."
John, who himself is a knight, will join a host of other European royals at what's being called the wedding of the century.
The famed singer, who remade his hit "Candle in the Wind" as a tribute to the late Princess Diana, commented that the future princess has a lot in common with the woman whose title she will assume.
Kate is "Diana in personality," John said. "She is very discreet, she is a very beautiful girl."
Of the couple, he said that, "they have been together a long time and I think she [Middleton] has handled the pressure so much."
He also voiced his hopes that William becomes king at a young age.
"I think we need young people like him to lead," John said. "I think he will be a tremendous king - not that Charles won't, but I think Williams will be...tremendous."