TOKYO (AP) — The American envoy to the United Nations called Friday for countries armed with atomic weapons to pursue nuclear disarmament as she visited the atomic bomb museum in Nagasaki, Japan.

Linda Thomas-Greenfield, who became the first U.S. cabinet member to visit Nagasaki, stressed the importance of dialogue and diplomacy amid a growing nuclear threat in the region.

“We must continue to work together to create an environment for nuclear disarmament. We must continue to prevent the spread of nuclear weapons in every corner of the world,” she said after a tour of the atomic bomb museum.

“For those of us who already have those weapons, we must pursue arms control. We can and must work to ensure that Nagasaki is the last place to ever experience the horror of nuclear weapons,” she added, standing in front of colorful hanging origami cranes, a symbol of peace.