"Kim would love to wed at Westminster Abbey but that won't be possible," showbizspy.com quoted a source as saying.
"Instead she's been looking at castles near London. She wants the most spectacular wedding and she's talking about having guests like Jay-Z and Beyonce, Eva Longoria, Lindsay Lohan, Rihanna and Katy Perry arrive in horse drawn carriages, just like the royal wedding," added the source.
Middleton will be bemused by Kardashian's plans.
When Kardashian was in London promoting her new fashion line recently, she sent Middleton some samples, but she turned her nose up at them.
Meanwhile, West is desperate to propose Kardashian, but feels like he has to wait until her divorce from Kris Humphries, her husband of 72 days, comes through.