Japan's Prime Minister Shinzo Abe arrives in Teheran today for a high-stakes two-day visit, as world leaders scramble to defuse rising tensions in the Middle East and to stop a nuclear deal from blowing up.
He is the first Japanese premier to visit Iran in 41 years.
While Japan and Iran tout their positive ties and mark the 90th anniversary of diplomatic relations this year, generations of Japanese leaders have been caught in the political crossfire between Iran and its security ally, the United States.
Mr Abe, joined by Foreign Minister Taro Kono, will meet Iranian President Hassan Rouhani this evening and Supreme Leader Ayatollah Ali Khamenei tomorrow.
"The Middle East is of crucial importance to Japan's energy security, and Iran is essential to the stability of the region," a senior Foreign Ministry official told reporters yesterday on condition of anonymity.
Mr Abe's trip follows a visit by German Foreign Minister Heiko Maas this week in a bid to salvage the 2015 nuclear pact. During Mr Maas' visit, Iran's top diplomat Mohammad Javad Zarif warned: "Reducing tension is only possible through stopping the economic war by America. Those who wage such wars cannot expect to remain safe."
The unfurling crisis stems from US President Donald Trump's decision last year to withdraw from the nuclear pact, and reinstate tough sanctions on Iran that have led to sharp inflation and a devaluation of the Iranian rial. This has hurt livelihoods and wiped out earnings.
Mr Trump has also threatened sanctions on any country that buys Iranian oil. Japan, which previously bought 5 per cent of its oil from Iran, has since stopped doing so.
Iran, in retaliation, has followed through on a threat last month to speed up its production of enriched uranium, International Atomic Energy Agency chief Yukiya Amano said on Monday. It has also threatened to blockade the Strait of Hormuz, through which a third of all crude supplies traded by sea passes.
Japan has split with the US to back the nuclear deal known as the Joint Comprehensive Plan of Action (JCPOA), which was signed by Iran, Russia, China, Britain, France, Germany and the United States.
Mr Abe, who has won Mr Trump's support for the visit, said last month with the US leader beside him: "The tension needs to be mitigated and alleviated, and should not culminate in armed conflict."
Still, Japanese officials, in a bid to tamp down expectations, have bristled at recent media portrayal of Mr Abe as a mediator or an interlocutor.
Dr Yasuyuki Matsunaga of the Tokyo University of Foreign Studies told The Straits Times that Japan's influence is limited as it is not a signatory of the JCPOA.
He added: "Since the fundamental problems that Iran is facing today is caused not by Iranian action or inaction, but by unilateral (actions by the) US, the true mediating work needs to be done in Washington DC, not in Teheran."
Keio University's Professor Koichiro Tanaka sees Mr Abe as caught between a rock and a hard place.
If Mr Abe is to show Japan's sincerity as a partner to Iran, he may have to "defy existing US sanctions on Iranian crude oil (as) anything short of that will not be sufficient to portray Japan's independent role".
If the trip does not go well, Prof Tanaka warned, "the hawks within the Trump administration could well (claim) that 'all diplomatic channels have been exhausted', and that the time for diplomacy is over".