Chris Jericho is scheduled to appear at next week's RAW and SmackDown tapings before going on tour with his band Fozzy in Europe. He will be touring with the band through the end of April, but he has been added to the RAW taping on April 22nd from the O2 Arena in London, England. It may just be an appearance for the local crowd, as he hasn't been added to any shows after that. Fozzy will be performing in London at the Electric Ballroom days later on Wednesday, April 24th.
As noted last week, The Undertaker will be at the SmackDown taping on April 23rd from the O2 Arena in London. The website of the arena is billing his appearance as "a London exclusive," so he likely will not be appearing on television.