Fans and festival goers have said that Paul McCartney could join popular singer Sir Elton John on stage at Glastonbury.

This comes after it was revealed that Elton John would be joined by four mystery guests with the identities of these being kept under wraps. 

Fans began theorising that The Beatles legend would join the Rocket Man singer on stage after Paul McCartney was spotted among the VIPs watching the Foo Fighters perform as their mystery band The Churnups.

While Paul McCartney was there to see the extremely popular rock outfit, some began to think that he was at the festival for another reason.

In December, Elton John was confirmed as the first Glastonbury 2023 headliner as he undergoes his last-ever tour.

A number of guests have been rumoured to join the star with names like Eminem and Billy Joel being among those tipped to appear on the Pyramid Stage.

Elton's husband David Furnish confirmed that there would be four mystery guests when speaking with Sky News this week, telling the broadcaster that he would have "four collaborators of his choosing."

Speaking on Twitter, one user speculated: “I’m thinking sir Elton is going to bring our Sir Paul McCartney and Eminem on Sunday by the way."

Another added: "Paul McCartney watching the Foo Fighters secret set at #Glastonbury23 … sticking around to play with Elton John on Sunday? What else are the rumours apart from Britney Spears?”

However, some fans wondered if Paul would instead collaborate with other headliners like Guns N' Roses with user writing: “So Paul McCartney was watching the Foos at side of the stage. Surely he’s there for “Live and Let Die” with Guns’N’Roses tomorrow?” 

Of headlining the festival, Elton admitted that he was "a little intimidated" by the prospect

Elton John will headline the Glastonbury Festival 2023 on Sunday, June 25.