A source close to the couple said they "have fallen in love with the U.K.," and have even started scoping locations.
"They are desperate to get married as soon as possible because they want to start a family and are slightly old-fashioned about these things," the source said. "The first place they thought of was Stonehenge, but they've also been looking at the Royal Pavilion in Brighton."
"Mila loves the idea of a stately home or something in the English countryside," the source said.
The source said the former "That 70s Show" costars are planning on keeping the ceremony low-key, with just a few family and friends.
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