Families of Japanese nationals abducted by North Korea have sought further cooperation in bringing their loved ones back home in a meeting with the US ambassador to the United Nations.

Ambassador Linda Thomas-Greenfield, who is visiting Japan, met the families at the prime minister's office in Tokyo on Thursday. They were joined by Chief Cabinet Secretary Hayashi Yoshimasa.

Thomas-Greenfield said she understands the families' pain and sense of loss. She promised that the US government will raise the issue at every opportunity and make efforts toward the return of all abductees.

Yokota Takuya, the younger brother of abductee Yokota Megumi and the head of a group of abductees' families, was accompanied by their mother Sakie and others. Megumi disappeared in 1977 when she was 13 years old.

Yokota Takuya said this grave violation of human rights has been going on for nearly 50 years. He emphasized the pressing need to act as the abductees' parents age.

He appealed to the United States not to ease its sanctions on North Korea, and to continue working with Japan.

Yokota Sakie said she desperately wants to see her daughter, whom she raised with much care and love.

She asked for continued support so that all the families can be reunited.