TOKYO -- Prime Minister Shinzo Abe appealed once again Thursday to U.S. President Donald Trump for assistance in resolving decades-old cases of Japanese citizens kidnapped by North Korea, which insists it has nothing more to show.
The two leaders spoke by phone before Trump announced that his highly anticipated summit with North Korea's Kim Jong Un will take place June 12 in Singapore.
During the phone call initiated by the White House, Abe congratulated the president on the safe return of three U.S. citizens who were held hostage by Kim's regime. Trump "appeared very eager to report the release of the Americans," said a Japanese government source present during the exchange.
Abe won a pledge from Trump in the U.S. last month to raise the subject of the Japanese abductees at his summit with Kim. During their meeting, Abe cited the cooperation between Tokyo and Washington in seeking the return of the American citizens, hoping that Trump will view the abductees in the same human rights context as the U.S. hostages.
Trump told the prime minister that he will do his utmost to achieve the best possible outcome for Japan during the Kim summit, Japanese Chief Cabinet Secretary Yoshihide Suga said to reporters on Thursday.
Relatives of the missing welcomed these developments.
"This is a credit to President Trump's resolute stance," said Akihiro Arimoto, whose daughter Keiko Arimoto was abducted in 1983 while studying in Europe. "I hope that we continue to head toward a resolution."
But circumstances surrounding the Japanese abductees differ from those involving the U.S. hostages. Washington kept tabs on the conditions and activities of the three citizens, which helped advance negotiations to secure their repatriation.
Of the 17 Japanese citizens who Tokyo says were kidnapped by North Korea over the years, five returned home in 2002. But officials have struggled to pin down the whereabouts of the rest. Pyongyang claims the cases are closed, declaring that the remaining 12 missing people -- including Megumi Yokota, who was snatched at age 13 and became the poster child for the abduction issue -- are either dead or never entered North Korea in the first place, among other explanations that Tokyo rejects.
Scores of others disappeared under similar circumstances, but their cases have not been recognized as abductions by the Japanese government. Keiko Ikushima, whose sister went missing in Tokyo in 1972, told an audience at a Japanese-sponsored event in New York last week that her mother "was watching TV of Japanese who were reunited and she mumbled, 'I will never experience this type of situation,' and passed away five months later."
North Korea promised a full investigation of cases involving missing Japanese as part of a May 2014 agreement made with Japan in Stockholm. But after Japan imposed tougher sanctions in February 2016 following a ballistic missile test, the Kim regime announced an end to the probe.
Abe, who accompanied then-Prime Minister Junichiro Koizumi on his landmark 2002 trip to North Korea -- which led to Pyongyang's admission of the abductions -- has repeatedly described resolving the abduction issue as his top priority.
Many analysts believe North Korea agreed to release the U.S. hostages in the face of American military pressure. Japan, lacking such threats, hopes to draw the Kim regime into a dialogue by dangling the possibility of economic aid.
Abe has said he is open to direct talks with Kim after the North Korean leader meets with Trump. But the Japanese leader insists that such a summit must produce results on the abductee issue.
Not all Americans held in North Korea were as fortunate as those who returned this week. Otto Warmbier, a university student arrested in 2016 while travelling North Korea, died last year soon after returning to the U.S. in a virtually brain dead state.
"The methods [North Korea] used -- hostage taking, torture, extrajudicial killing -- are the methods they've been using for the last 30 or 40 years," his father Fred Warmbier said at the New York event. "It's not changed. North Korea hasn't changed."
Nikkei staff writer Ariana King in New York contributed to this article.