Georg Ratzinger, brother of Pope Benedict XVI

Georg Ratzinger, brother of Pope Benedict XVI, speaks to reporters Monday at his home in Regensburg, Germany. (Armin Weigel / European Pressphoto Agency / February 11, 2013)

LONDON -- Pope Benedict XVI's decision to step down may have taken almost everyone by surprise Monday, but one person said he had known such a move was likely: his older brother.

Georg Ratzinger, 89, told the German DPA news agency that Benedict increasingly felt his physical limitations. The pope's doctor had advised him against any further transatlantic journeys, and walking had become more difficult, Georg Ratzinger said.

PHOTOS: Pope Benedict XVI to step down

Deciding to retire was a "natural step," the elder Ratzinger told DPA.

"My brother wants to have more rest in his old age," he said.

The two men grew up in Bavaria and attended seminary together outside the town of Traunstein.

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