The country also promised further steps, including the closure of its main Yongbyon nuclear complex, Moon said following his summit with the North's Kim Jong Un.
Roth told Reuters he was deeply frustrated with dictator Kim Jong-un's reticence to engage the issue because addressing sexual abuse would pose no threat to his power, it would raise his stature in the global community, and it would help North Korea open its economy to the outside world as Kim desires.
"North Korean women would probably say, "Me Too" if they thought there was any way to obtain justice, but their voices are silenced in Kim Jong-un's dictatorship".
Kenneth Roth, Human Rights Watch's executive director, speaks during a news conference in Seoul, South Korea.
The report comes as US -led global diplomacy focuses on North Korean nuclear disarmament.
The Japanese government has maintained that the right to seek compensation was terminated under a 1965 bilateral treaty, which stipulates that issues relating to property and claims between the two countries and their peoples have been settled "completely and finally".
Roth urged the North Korean government to acknowledge the problem and ensure that police and prosecutors in the courts treat sexual violence as a serious crime, "rather than sweeping it under the rug". A 2016 dispatch said every woman in the North is "highly valued and respected" and that they "all can lead a worthwhile life as a heroine of the times".
"Every night, some woman would be forced to leave with a guard and be raped", a former trader in her 30s who was detained in a holding center told Human Rights Watch.
Almost everyone in North Korea is subject to abuse by the brutal Communist regime, but the report argues women are exceptionally vulnerable because corrupt soldiers and government officials demand sexual favors as bribes.
Even in the military, officials "demand sexual favors", she says.
Like all the women cited in the report, Yoon is referred to by a pseudonym to protect her identity and any relatives in North Korea. "It was the sound of the key of the cell of our prison room opening".
South Korean court to rule on war survivors' claim against Japanese firm
He said the ruling violated a 1965 treaty between Seoul and Tokyo that was accompanied by Japanese payments to restore diplomatic ties.
"Click, click, click was the most disgusting sound I ever heard", Yoon was quoted as saying in the report.
Most of the assaults reported to HRW took place when the victims were in custody or when the victims were market traders who were attacked by market guards or other officials.
Traders who smuggle goods across the border with China to sell at state-sanctioned private markets are forced to pay "bribes" including sexual favours, the report said.
Women who talked to the AP said they did not even know what exactly sexual abuse was when they were in North Korea.
"Higher-level male (army officers) often patted female soldiers on their hips and breasts or put their hands underneath their uniforms around their necks when they passed by them". "They consider us toys".
The US and South Korea have carefully avoided confronting Kim head-on over rights issues.
A second woman said a detention centre guard tried to rape her but moved away after she said her body was crawling with lice.
Roth further contextualized the problem facing those in North Korea, saying women "feel a frightful combination of powerlessness to escape sexual abuse and violence, but also shame when they are victimized".
The nuclear-armed North, which is accused of widespread rights abuses by the United Nations and other critics, is a deeply hierarchical and patriarchal society where traditional values of deference to authority still hold sway. "If the agreements are well carried out, it will contribute to not only the improvement of inter-Korean relations and peace settlement on the Korean peninsula but also the improvement of human rights of North Korean people", the message said.
"When we think about the North's disgusting rights conditions, I know we should tackle that issue right away but it's also something that we can't resolve overnight", said analyst Cho Han Bum at Seoul's Korea Institute for National Unification.