Tomas Ojea Quintana, the visiting U.N. special rapporteur on North Korea, said he will make every effort to resolve the abduction issue.

“I will commit myself” to making progress on the issue, Ojea Quintana said Thursday at a Diet meeting with a cross-party group of lawmakers seeking the return of Japanese who were abducted by North Korean agents in the 1970s and 1980s.

“We want to ask the United Nations to give further weight to the abduction issue,” former economy minister Takeo Hiranuma, who leads the group, said as the meeting began. The session was open to the media.

Ojea Quintana’s visit comes amid concerns among the abductees’ relatives that the global condemnation issued in response to the North’s fifth nuclear test and ballistic missile tests will stall bilateral negotiations on the abduction issue.

The lawmakers and Ojea Quintana discussed the possibility of referring the matter to the International Criminal Court, a lawmaker who attended the meeting said.

But the U.N. special rapporteur noted that there is one country on the U.N. Security Council that does not support the ICC option, the lawmaker said.

Ojea Quintana, an Argentinian lawyer with extensive human rights experience who assumed the U.N. post in August, began his four-day visit to Japan on Wednesday after a visit to South Korea.

He is set to report on his discussions in Japan and South Korea to the U.N. Human Rights Council in March next year.

Japan officially lists 17 nationals as abductees but suspects Pyongyang’s involvement in many more. Five of the 17 were repatriated in 2002.

Tokyo has been urging Pyongyang to report on the results of its latest probe into the whereabouts of all Japanese residing in North Korea, as stipulated under a bilateral agreement, but no tangible progress has been made.

The abduction issue has prevented the two countries from normalizing diplomatic relations.