While North Korea has already this year held summit talks with its neighbors South Korea and China as well as the United States, its leader Kim Jong Un has shown no signs of meeting with Japanese Prime Minister Shinzo Abe anytime soon.

Instead of merely having no interest in starting dialogue with Japan, Pyongyang has steadfastly lambasted its longtime adversary with the intention of fanning nationalistic sentiments domestically and strengthening ties with Seoul.

As Japan-North Korea relations are expected to deteriorate more than ever, Tokyo "should not hope that an Abe-Kim summit will take place in the near future," a source familiar with Pyongyang's thinking said.

On Friday night, Japanese Foreign Minister Taro Kono chatted with his North Korean counterpart Ri Yong Ho on the sidelines of a series of Association of Southeast Asian Nations-related gatherings in Singapore.

It was the first ministerial contact between the two countries since Abe began to explore the possibility of a meeting with Kim following the first-ever U.S.-North Korea summit in June in the city-state.

Although Kono told reporters that he informed Ri of Japan's views and basic stances, he declined to disclose further details, suggesting their conversation may not have been held in an amicable atmosphere.

As Abe wants to talk with Kim bilaterally on the occasion of international conferences in September, Kono was "urged" by the prime minister's office to make contact with Ri in Singapore, a Japanese Foreign Ministry source said.

Kono, however, was "not able to obtain any results, or might have even worsened the situation," the source added.

While improving relations with other countries like South Korea and the United States, North Korea has recently stepped up criticism of Abe's government, asking Japan to atone for its past military occupation and colonial rule on the Korean Peninsula.

"Acerbic comments on Japan are a cohesive to bring North Koreans together and to demonstrate Chairman Kim's nationalist credentials," said Stephen Nagy, a senior associate professor of politics at International Christian University in Tokyo.

"Japan represents a historical experience that helped shape the emergence of a North Korea, the division of the peninsula and today's nuclear standoff," said Nagy, also a fellow at the Asia Pacific Foundation of Canada.

"These are all part of the North Korean identity now as they have been engrained and exaggerated in several generations of North Koreans. It will be difficult to change this view of Japan as it is so divorced from Japan today," he added.

Tong Zhao, a fellow at the Carnegie-Tsinghua Center for Global Policy in Beijing, said North Korea is unlikely to try to get along with Japan soon, given that Abe continues to take a hardline stance on Pyongyang.

Even after the historic summit between Kim and U.S. President Donald Trump, Abe's government has repeatedly argued that international sanctions against North Korea should be maintained until Pyongyang achieves complete denuclearization as promised.

"As South Korea, Russia, and China have all taken a more flexible approach to engage with North Korea, Japan naturally becomes the next 'nut' for North Korea to crack," Zhao said.

Malcolm Cook, a senior fellow at the ISEAS-Yusof Ishak Institute in Singapore, said Japan-North Korea relations "may not improve as long as Japan keeps its full range of sanctions on North Korea."

Tokyo and Pyongyang have also been divided over the issue of past abductions of Japanese nationals by North Korean agents, with Abe having said that tackling the matter is his "life's work."

Japan claims that 17 of its citizens were abducted in the late 1970s and early 1980s, five of whom were repatriated in 2002, and suspects North Korea was involved in many more disappearances.

But Pyongyang has said eight of the 17 -- including Megumi Yokota, who disappeared while heading home from school when she was 13 -- have died and four never entered the country.

"What (is) sought by Japan in persisting in talking about the worn-out 'abduction issue' is to use the issue as an excuse for evading the liquidation of the past and a political slogan for the hostile policy toward" North Korea, the Rodong Sinmun of the ruling Workers' Party said last month.

Japan has insisted it will make efforts to resolve several matters such as the abduction issue before normalizing ties with North Korea based on the "Pyongyang Declaration," a key diplomatic document signed by the two nations in 2002.

"I'm wondering why Japan hasn't tried to solve the abduction issue after normalizing relations with North Korea," a diplomat at an embassy in Beijing of a European country said.

"Unless the Japanese government changes its policy, it cannot break down the status quo," the diplomat said.

Abe has been looking to hold a face-to-face meeting with Kim possibly in September on the fringes of the Eastern Economic Forum in Russia's Far Eastern city of Vladivostok or the U.N. General Assembly in New York.