The co-chair of Nihon Hidankyo, the winner of this year's Nobel Peace Prize, has asked high school students to think about what should be done to build a future free of nuclear weapons.

Tanaka Terumi from the Japanese group representing atomic bomb survivors of Hiroshima and Nagasaki visited a high school in Saitama City, near Tokyo, on Wednesday. It was his first speech since the group was awarded the prize.

The 92-year-old, who lives in Saitama Prefecture, was at his home in Nagasaki City when the atomic bomb exploded. He was 13.

During the speech, Tanaka said he had not really expected his group would receive such an honor.

Looking back, Tanaka said, it was a good decision after all. He noted that he and other members have worked hard in the belief that nuclear weapons should never be used again amid the increasingly severe international situation.

Tanaka urged the students to learn how humans were harmed by nuclear weapons, which can kill hundreds of thousands of people at one time.

Tanaka also asked for their strong determination to never repeat the tragedies of nuclear weapons.

One student said it was a serious speech, and different from what he learned on the internet and through books. He added he realized that atomic bombs are frightening and should never be used again.

Another student said he did not understand the reality of nuclear bombs until he heard Tanaka's speech. He said he should have known better.

The student noted that Japanese people can state their messages as the world's only atomic-bombed country. He added that this year's Nobel Peace Prize will change the people's mindset.

The Saitama high school students are scheduled to visit Hiroshima next month.