In an interview aired Friday with the Mexican broadcaster Televisa, he said: "I have the sensation that my pontificate will be brief: Four or five years. I don't know. Or two or three. Well, two have already passed."
Francis has previously said he thought he'd be pope for two to three years.
He said the thing he missed most was being able to go out to get pizza undetected.
At Mass later Friday, Francis also announced a special Jubilee Year to focus the church on his main priority: mercy. It's only the 27th time in the history of the Roman Catholic Church that there has been a Holy Year.
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