Japan's government is looking into re-opening official talks with North Korea to resolve questions over the abductions of Japanese citizens decades ago, raising concerns among allies who fear Tokyo's focus on that issue might weaken efforts to reign in Pyongyang's nuclear weapons program.

Chief Cabinet spokesman Yoshihide Suga said Wednesday that high-level talks with the North are possible if they would lead to a breakthrough on the abductions. Prime Minister Shinzo Abe indicated earlier this week he is open to holding a summit with North Korean leader Kim Jong Un if such a breakthrough could be made.

Abe dispatched a senior adviser to Pyongyang last week, catching Seoul and Washington off guard. Both said they were not given prior notice.