Pope Benedict XVI , 81, has said he is looking forward to a "peaceful old age" with "serenity and humility" as he enters ''the last phase'' of his life.

The Pope made his remarks at a ceremony making Father Georg Ratzinger, his brother, who is three years older, an honorary citizen of Castel Gandolfo, the papal summer residence in a hilltop town above Lake Albano south of Rome.

''We have arrived at the last stage of our lives, at old age, and the days left to live grow progressively fewer,'' the pontiff observed. ''But even at this stage my brother helps me to accept the weight of each day with serenity, humility and courage. For this I thank him".

He added: ''From the beginning of my life my brother has always been not only a companion for me but a trustworthy guide, a point of reference with the clarity and determination of his decisions. He showed me the road to take, even in difficult situations,'' he added.

The Pope took a two week break with his brother this summer at a seminary at Bressanone in the mountains of northern Italy. He spent the time playing the piano, walking, and preparing his next encyclical as well as the second volume of his study of Jesus. In September he is to travel to France to pray at the Marian shrine at Lourdes.