The grandson of former U.S. President Harry Truman is in Japan to discuss the atomic bombs dropped on Hiroshima and Nagasaki, just ahead of the 67th anniversaries of those momentous events that ended World War II.

Clifton Truman Daniel, 55, spoke with bomb survivors as well as students at a forum in Tokyo University on Friday, making him the first relative of the president to ever attend the commemorations.

A former journalist, Daniel was invited by Japanese anti-nuclear groups.

 "The most impressive thing is that survivors and students and all of us can come together and talk, and they can share their stories," he told Agence France Presse, adding the meetings were "a good first step toward healing old wounds. We are looking at this ... as a good first step to talk and to better understand each other".

Nonetheless, Daniel defended his grandfather’s decision to drop the bombs.

"I can't second-guess my grandfather ... (but) there is no right decision in war," he said. "My grandfather always said that he made that decision to end the war quickly. That's what he believed. (He) was horrified by the destruction caused by those weapons and dedicated the rest of his presidency trying to make sure that it didn't happen again. I hope that I can do the same, to work to hopefully rid the world of nuclear weapons.”

Up to a quarter of a million people died in the bombings of Hiroshima and Nagasaki.