UK-based website The Sun is reporting:

LED ZEPPELIN frontman ROBERT PLANT is to be given an ultimatum by his bandmates – join us on tour or we’ll replace you.

Zep guitarist JIMMY PAGE, bassist JOHN PAUL JONES and drummer JASON BONHAM have been busy recently rehearsing in West London’s Ritz Studio and using stand-in vocalists.

And one American singer has been so impressive the other band members are confident they could hit the road next year WITHOUT their iconic frontman.

Brummie-born belter Plant has refused to take part in any practice sessions as he is currently committed to his side project with country singer ALISON KRAUSS.

A source said: “Jimmy, Jason and John are determined a tour will go ahead next year.

“They’ve been rehearsing frequently in London and the band is really gelling.

There’s an American guy who has been standing in for Robert regularly and doing a great job.

“Obviously they want the original frontman to join them on the road but he still won’t commit.

“They will be finalising plans for shows over the next couple of months and will tell Robert that if he doesn’t want to be involved they will go ahead without him.”

While fans would be disappointed if Plant was not involved, the shows would still fill arenas worldwide.

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