U.S. President Barack Obama's recent visit to Hiroshima provided a precious opportunity for the American public to think about the goal of creating a world free of nuclear weapons, a senior U.S. government official said Tuesday.

Rose Gottemoeller, undersecretary of state for arms control and international security, told Kyodo News and other media outlets in Vienna that the day of Obama's visit to Hiroshima on May 27 was "an incredibly moving day."

"I think it was a very important opportunity for the American public to help them to think about the continuous goals" toward a nuclear-free world as set out by Obama in a famous speech in Prague in 2009, she said.

Gottemoeller said she was delighted to see the visit — the first by a sitting U.S. president — and the history of attacks on Hiroshima and Nagasaki widely reported by the U.S. media.

"I think the visit to Hiroshima was an important chance for the American public to focus on these issues and to both recollect history and reflect upon it and to think about the necessity in the future of continuing to press for nuclear disarmament," she said.

Obama paid the visit to Hiroshima when he traveled to Japan to attend the annual summit of the Group of Seven industrialized nations in central Japan on May 26-27.

The United States dropped an atomic bomb on Hiroshima on Aug. 6, 1945, and a second on Nagasaki three days later. Around 210,000 people are estimated to have died as a result of the attacks by the end of 1945. Japan surrendered on Aug. 15 of the same year, bringing an end to World War II.

Gottemoeller was in Vienna to attend a ministerial-level meeting Monday to commemorate 20 years since nations began signing the Comprehensive Nuclear Test Ban Treaty.