The 85-year-old announced the decision in Latin during a meeting of Vatican cardinals this morning.
He said that because of his age and diminishing strength, he didn't feel he could carry on.
On the Island, Lord Bishop Robert Paterson has described the Pope as having a formidable intellect but also formidably conservative.
He admits the resignation has come as a surprise:
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Minister says figure was to ensure premises deemed not commercially viable could be included in rollout
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