The United States told Japan that it had been reluctant about the possibility of Hiroshima hosting next year's Group of Seven summit out of concern about reactions by Americans, a U.S. government official said Sunday.

Some in Japan hope U.S. President Barack Obama, a Nobel Peace Prize laureate who seeks a world free of nuclear weapons, will visit Hiroshima or Nagasaki when he visits Japan for the 2016 G-7 summit.

The story revealed by a U.S. official indicated, however, that it is harder than generally thought in Japan for such a trip to take place.