TOKYO — Pope Francis arrived in Japan on Saturday, where he is expected to deliver a robust anti-nuclear message of peace in the only country to have suffered an atomic bomb attack.

The 82-year-old Argentine is fulfilling a long-cherished ambition to preach in Japan, where years ago he hoped to be a missionary.

He arrived in Tokyo in heavy rain and high winds, the white cape of his papal outfit blowing up around his face as he stepped gingerly down the staircase from the Thai Airways plane that carried him from the first stop of his tour in Thailand.

His four-day trip will begin with visits to Nagasaki and Hiroshima, cities forever associated with the nuclear bombs dropped on them at the end of World War II, killing at least 74,000 people and 140,000 people respectively.

In a video message to the Japanese people before he left the Vatican, Francis railed against the "immoral" use of nuclear weapons.

"Together with you, I pray that the destructive power of nuclear weapons will never be unleashed again in human history," said the head of the world's 1.3 billion Catholics.

Francis arrives from Thailand, where he preached a message of religious tolerance and peace.

He is expected to do the same in Japan, a country with only approximately 440,000 Catholics out of a population of 126 million.

Francis will visit Hiroshima and deliver remarks at the world-famous peace memorial that marks the day on Aug. 6, 1945 when the atomic bomb was dropped.

Father Yoshio Kajiyama, director of the Jesuit social center in Tokyo, was born in Hiroshima shortly after the war and is eagerly awaiting the pope's anti-nuclear speech.

"My grandfather died the day of the bomb in Hiroshima, I never knew him. Four days later my aunt died when she was 15 years old," said the 64-year-old.

"If you grow up in Hiroshima, you can't forget the bomb."

In Tokyo on Monday, Francis will met victims of the "triple disaster", the earthquake, tsunami and nuclear meltdown in 2011 that devastated large swathes of north-eastern Japan.

His trip will also include meetings with the new Emperor Naruhito and Japanese Prime Minister Shinzo Abe, as well as delivering a mass in a Tokyo baseball stadium. -AFP