Shotaro Yachi, head of the secretariat at the National Security Council, has held negotiations with political heavyweights in China and Russia - serving at times as a "secret envoy" for Prime Minister Shinzo Abe, who highly values diplomatic ties with the two countries.
"Are you a close aide to Prime Minister Abe, Mr. Yachi? You're famous here in China."
So said Chinese State Councillor and chief diplomat Yang Jiechi to Yachi before dawn last Nov. 7, as the two held last-minute negotiations at the Diaoyutai State Guesthouse in Beijing for a Japan-China summit meeting.
The meeting was held three days later, the first summit between the two countries in about three years.
Late the previous night, foreign officials from both sides had prepared a draft of a four-point memorandum describing their separate perceptions about history and the present situation regarding the Senkaku Islands. The meeting between Yachi and Yang started at 1 a.m., and they compiled a final draft acceptable to both sides.
Abe had advised Yachi beforehand not to make any unnecessary compromises merely to realise a summit meeting. The meeting lasted for about an hour, until past 2 a.m. During that time, Yachi telephoned Abe at the prime minister's official residence to obtain his approval for specific expressions used in the document.
Yachi served as vice foreign minister in the first Abe Cabinet, which was inaugurated in 2006. Abe nominated him as the first head of the NSC secretariat - launched in January 2014 as the command centre for foreign and security policy - due to his firm trust in Yachi's views on international affairs.
With the NSC's creation, Abe established a system to end sectionalism among related ministries and agencies - such as the Foreign Ministry - and oversee foreign policy from the helm of the Prime Minister's Office.
The "closeness" of negotiators to power plays a significant role in the negotiations with China and Russia, which operate under authoritarian leadership. Due to Yachi's excellent relationship with the prime minister, communications with his counterparts tend to go smoothly.
Former Prime Minister Yasuo Fukuda, who has personal connections in China, secretly visited the country last July and met Chinese President Xi Jinping to urge him to hold a summit meeting. Yachi was present for their discussion on Abe's intentions.
"China understood how serious the Japanese side was, since a right-hand man of Prime Minister Abe accompanied Mr. Fukuda," a senior Japanese government official said. "This is how Japan successfully paved the way for the summit meeting."
On July 7, Yachi was in Moscow to meet Nikolai Patrushev, secretary of Russian President Vladimir Putin's Security Council, to coordinate a visit to Japan by Putin within the year.
Naoya Imai, a secretary to the prime minister who is in charge of parliamentary affairs, is a key player in Japan's diplomacy with Russia. Imai boasts years of experience in the energy field, and came to the post from the Economy, Trade and Industry Ministry. Well-versed in affairs related to Europe and Russia, he has cemented his own personal ties with politicians and senior officials of these countries.
Abe normally makes diplomatic decisions after being briefed on the latest developments by Foreign Minister Fumio Kishida and Vice Foreign Minister Akitaka Saiki, as well as Yachi and Imai. Their opinions are often split during discussions on policies concerning Russia.
On May 9, Russia held a ceremony in Moscow to commemorate the 70th anniversary of its victory over Germany. Imai had proposed the idea of Abe visiting Russia around that time so as to bolster bilateral relations. But Yachi and others opposed the idea, mainly due to its potential impact on ties with the United States, which Abe would be visiting immediately before.
Just 12 hours before the Japan-US summit meeting on April 28, it was announced that the Russia trip had been aborted. Out of consideration for the Russian president, Abe sent a personal note to Putin to express his regret at not being able to attend the ceremony.
When it comes to the handling of diplomatic matters, there is a general consensus that the prime minister takes his aides' opinions into consideration and makes his own decisions in the end. But there was one occasion on which Abe did not listen to his aides at all: when he visited Yasukuni Shrine at the end of 2013.
The prime minister called his failure to visit Yasukuni Shrine during his first Cabinet "a matter of deepest regret." Explaining that he "vowed never to fight a war again," Abe realised a personal wish in visiting the shrine. But the US government expressed "disappointment" regarding the move, which also drew criticism from the Chinese and South Korean governments.
When Abe informed his aides of his plans, they urged him to reconsider for fear of causing a diplomatic row. They urged the prime minister to visit the shrine at the end of his term if he must, but Abe insisted on going.
Abe reportedly told a close aide, "You can only say such things because you're not a politician."