Pope Benedict XVI announced Monday that he would resign Feb. 28.
Talking from his home in Regensburg to the news agency dpa, Georg Ratzinger said his brother was having increasing difficulty walking and that his resignation was part of a "natural process."
"His age is weighing on him," the 89-year-old said of his 85-year-old brother. "At this age my brother wants more rest."
Georg Ratzinger did not answer his telephone for calls seeking further comment.
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