Japan's chief envoy in negotiations with North Korea on Friday told families of Japanese nationals suspected of being abducted by North Korean agents more than 10 years ago that Japan will do its best to resolve the cases.

"We cannot view the current negotiations between Japan and North Korea in an optimistic light but we would like to do our best," Kojiro Takano said during a visit to the home of 72-year-old Hidekazu Hasuike in Kashiwazaki, Niigata Prefecture.

Hasuike's son, Kaoru, then 20, and his friend Yukiko Okudo, 22, went missing from Kashiwazaki on July 31, 1978.

"Dialogue . . . aimed at resolving the abduction issue is the best method at this point in time," Takano said.

He said he will visit the former homes of all Japanese nationals suspected of being abducted.

Hasuike said: "I want (my son) to come back safely. If anything, I just want to know whether he's doing OK."

Police suspect at least 10 Japanese nationals were abducted by North Korean agents in the 1970s and 1980s. Pyongyang has denied the allegations.

Harunori Kojima, head of a group calling for the rescue of abducted Japanese nationals, including Megumi Yokota, who disappeared from Niigata Prefecture as a 13-year-old in 1977, asked Takano to make the alleged abductions a top priority with North Korea.

Kojima said the government should not engage in negotiations aimed at normalizing ties with North Korea until the issue is resolved.

In April, Japan and North Korea resumed normalization talks with Pyongyang for the first time since negotiations collapsed in 1992.

In the latest negotiations, North Korea called for an apology from Japan and asked for compensation for wartime atrocities as a condition for normalizing ties.

Japan, meanwhile, insisted the issue of the alleged abductions be resolved before ties are established.