Japan's top government spokesperson says Pyongyang's claim that the issue of abductions of Japanese nationals by North Korean agents is already settled is absolutely unacceptable.

Chief Cabinet Secretary Hayashi Yoshimasa told reporters on Friday that the government takes note that the sister of North Korean leader Kim Jong Un issued a statement about a potential visit by Japanese Prime Minister Kishida Fumio to Pyongyang.

Kim Yo Jong said in the statement on Thursday that the visit would be possible if Japan "does not lay such a stumbling block as the already settled abduction issue in the future way for mending the bilateral relations."

Hayashi said he will refrain from making detailed comments, including the government's evaluation of the statement, as it could affect future negotiations.

He also said Japan remains unchanged in its stance to seek a comprehensive solution to pending bilateral issues, such as the abductions and North Korea's missile and nuclear programs, based on the 2002 Pyongyang Declaration between Japan and North Korea.