UPDATE 1-Pope calls nuclear weapons possession indefensible and perverse

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NAGASAKI, Nov 24 (Reuters) - Pope Francis, speaking in one of the only two cities hit by atomic bombs in history, appealed for the abolition of nuclear weapons on Sunday, saying their mere possession was perverse and indefensible.

"The possession of nuclear and other weapons of mass destruction is not the answer (to longings for peace)," Francis said in a message delivered at Nagasaki's Atomic Bomb Hypocenter Park, ground zero of the bomb the United States dropped on Aug. 9, 1945, instantly killing 27,000 people.

"Our world is marked by a perverse dichotomy that tries to defend and ensure stability and peace through a false sense of security sustained by a mentality of fear and mistrust," he said, speaking in a driving rain.

"Peace and international stability are incompatible with attempts to build upon the fear of mutual destruction or the threat of total annihilation," he said. He also decried what he said was a dismantling of non-proliferation treaties.

Nagasaki was the second city to be hit by an atomic bomb during World War Two. Later on Sunday, the pope was due to visit Hiroshima, site of the first blast, which instantly killed about 78,000 people.

About 400,000 others eventually died of radiation illness and injuries caused by the two bombs, which the United States dropped in an effort to end the war. (Reporting By Philip Pullella, editing by Elaine Lies)