Japanese Prime Minister Shinzo Abe spoke with US President Donald Trump over the phone on Tuesday (June 11) to discuss Iran, one day before the premier's three-day trip to the Islamic Republic amid mounting tensions between Washington and Tehran.
Mr Trump and Mr Abe "exchanged views on regional situations, including the one in Iran," Japan's government spokesman Yoshihide Suga told a news conference.
Mr Abe, who will become the first Japanese premier to visit Iran in 41 years, is due to hold talks with Iranian Supreme Leader Ayatollah Ali Khamenei and President Hassan Rowhani during his stay, Mr Suga said.
Mr Abe's trip to Iran comes when this year marks the 90th anniversary of diplomatic relations between the two countries, Mr Suga added.
Mr Abe is willing to serve as an intermediary, as Japan has friendly relations with Iran, which the country has long relied on for oil imports.
Mr Abe is in a unique position, thanks to his close ties to Mr Trump, cultivated since the US leader took office, and Tokyo's friendly relations with Iran, diplomatic experts said. "Abe is trying to play the role of messenger and ease the tension," said Mr Toshihiro Nakayama, a Japan Fellow at the Wilson Centre in Washington.
"It is a bold move. I think it comes from confidence with his personal relations with Trump."
Japan is keen for stability in the Middle East because it imports the bulk of its oil from the region, although it stopped buying Iranian oil this year because of US sanctions.
Some experts played down prospects for the trip.
"The object of the visit is not to mediate," said former Japanese diplomat Kunihiko Miyake. "It's basically bilateral issues and if there is any additional business to do, we will do it carefully."
The most Mr Abe can probably achieve is to persuade Iran and the US to resume direct talks, the experts said, adding that both sides may be seeking a face-saving way out of the confrontation.
"The situation in the region here is highly explosive and extremely serious," German Foreign Minister Heiko Maas told a news conference in Tehran on Monday alongside Iran's foreign minister, Mohammad Javad Zarif.
"A dangerous escalation of existing tensions can also lead to a military escalation."
Mr Maas was the most senior Western official to visit Iran since the new war of words with Washington erupted last month.
In his meeting with Mr Maas, President Hassan Rouhani blamed the US for the soaring tension and called on the European signatories to the deal to "resist the economic war on Iran imposed by America".
