When asked if he understood he would never be released from prison, Ariel Castro said: "I do understand that, your honor."
He added, "I knew I was pretty much going to get the book thrown at me."
The deal comes more than a month after a statement issued on behalf of the women said they were "hopeful for a just and prompt resolution" and had "great faith in the prosecutor's office and the court."
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Mayor of London Sadiq Khan is backing the scheme.
Sunday will be a fine day across much of Scotland and northern England, with much less coastal mist and low cloud than yesterday.
A spokesperson said the lightning strikes had left the "aircraft fuelling system unavailable."