U.S. Secretary of State John Kerry has sent a letter of appreciation to the director of the Hiroshima Peace Memorial Museum for hosting him during the top U.S. diplomat's visit in April, museum officials said Friday.

Kerry was the first U.S. secretary of state to travel to Hiroshima, which was devastated by a U.S. atomic bombing on Aug. 6, 1945. Kerry's trip served as a prelude to a historic visit by President Barack Obama late last month.

The letter, dated May 3 and addressed to museum director Kenji Shiga, reached the museum through the U.S. Embassy in Tokyo.

"Visiting the memorial and remembering the stark realities of war affirm the importance of our work toward peace in a world free from the threat of nuclear weapons," Kerry wrote.

The museum exhibits a number of artifacts of atomic bomb victims and other items related to the world's first nuclear attack.

Regarding a book on the museum titled "The Spirit of Hiroshima," a copy of which Shiga gave to Kerry during his visit, the secretary of state said it was "a reminder of the powerful experience I had at the museum."

Shiga said, “I am happy that he looked through the book.”

On April 11, the final day of the two-day Group of Seven foreign ministerial meeting in the city, Kerry toured the museum along with other G-7 ministers.