Most hibakusha surveyed think Japan should join the U.N. treaty banning nuclear weapons, underscoring their discontent with the government’s opposition to the agreement.

The results of the survey by Kyodo News, released Saturday ahead of the 73rd anniversary of the atomic bombings next month, also showed that more than 60 percent of the survivors do not discuss their experiences due to old age or reluctance to remember the details of the aftermath.

The issue of passing on the memory of the 1945 bombings has become more urgent as the ranks of those who witnessed the horrors firsthand decline.

The world’s first nuclear attack, at Hiroshima on Aug. 6, 1945, and the second at Nagasaki three days later, ended up killing an estimated 214,000 people by the end of that year.

The June survey covered about 6,000 survivors nationwide and drew 1,450 valid responses. Of the respondents, 80.8 percent urged the government to sign the landmark treaty, citing Japan’s unique position as the only nation to have been attacked with atomic weapons.

In July last year, the U.N. approved the Treaty on the Prohibition of Nuclear Weapons, and included a reference to the “unacceptable suffering” of the victims of the A-bombings. The global accord had the support of 122 countries.

But it was not backed by any of the five permanent members of the U.N. Security Council — Britain, China, France, Russia and the United States — because all are nuclear powers.

Japan, which relies on the U.S. nuclear umbrella for its security, also declined to sign it.

One of the respondents, a 76-year-old man, said the government’s position “ignores the atomic bomb victims’ years of efforts” to rid the world of nuclear arms.

While 80.2 percent welcomed the treaty, 4.8 percent said otherwise, with many skeptical about its effectiveness without the backing of nuclear weapons states.

More than seven decades on, 950 of the survivors, or 65.4 percent, said that they still do not discuss the bombings.

“I do not want to remember the hell I saw that day, that moment,” a 92-year-old man said.

Among the 440 survivors who said they do discuss the bombings, a majority expressed concern that their efforts to convey their experiences to younger generations could be halted by failing health.

Tensions over North Korea’s nuclear weapons program have been easing in the wake of the historic inter-Korean summit in April. About 35 percent of the respondents said they were hopeful the goals set at the denuclearization summit would be achieved.