Plant has refused to take part in any practice sessions as he is currently committed to his side project with country singer Alison Krauss. "Jimmy, Jason and John are determined a tour will go ahead next year," The Sun quoted a source, as saying.
"They've been rehearsing frequently in London and the band is really gelling. 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," the source added.