US Secretary of State John Kerry will visit Hiroshima, the Japanese city devastated by an American atomic bomb, later this month as part of preparations for the G7 summit.
Kerry will join ministers from the other members of the club of leading democracies in the city on April 10 and 11 to work on the agenda for the Group of Seven leaders' summit in May.
US officials are still considering a possible visit to Hiroshima by President Barack Obama during his trip to Japan for the meeting, but no announcement has been made.
The State Department said Kerry would make the trip after attending a ministerial meeting of the Gulf Cooperation Council in Bahrain on April 8 and 9.
Japan has long urged world leaders to visit Hiroshima and Nagasaki to see the horrors of the atomic bombings and join efforts to eradicate nuclear arms.
But the most senior US official to have visited Hiroshima -- which was consumed in the world's first nuclear attack on August 6, 1945 -- has been House Speaker Nancy Pelosi.
Last month, Japanese government spokesman Yoshihide Suga said: "The government has always called on leaders around the world to visit Hiroshima and Nagasaki to see for themselves the reality of atomic bombings.
"We believe (visits) are important to boost international momentum toward achieving a world without nuclear arms."
The world's first atomic bomb killed about 140,000 people in Hiroshima, including those who survived the explosion itself but died soon after due to severe radiation exposure.
Three days later, the US military dropped a plutonium bomb on the port city of Nagasaki, killing some 74,000 people.
The bombings are controversial in the United States, where opinion remains divided over whether their use in the closing days of World War II was justified.