Pope Francis is eager to deliver a message from one of Japan's two atomic-bombed cities that the making of nuclear weapons — not just their use or possession — is unethical, according to a Japanese Catholic source.

The pope plans to visit Japan in November, making him the first pontiff to travel to the country since John Paul II nearly 40 years ago. He may also go to Hiroshima and Nagasaki — the cities that suffered U.S. atomic bombings in the final days of World War II.

Referring to the pope's ongoing efforts to call for a world without nuclear weapons, the source said, "The pontiff is expected to go a step further."