TOKYO－Japan's Prime Minister Shinzo Abe is expected to visit Iran this week on a rare diplomatic mission, hoping to ease tensions between Teheran and Tokyo's key ally Washington.

Iran is locked in a bitter standoff with the United States after US President Donald Trump withdrew from a landmark nuclear deal last year.

Washington has now reimposed sanctions and shifted troops to the region, putting military and economic pressure on Iran, including forcing US allies like Japan to stop purchasing Iranian oil.

Japanese government officials said Abe will not present Teheran with a list of demands, or deliver a message from Washington, and instead wants to position Japan as a neutral intermediary.

That could prove useful, said Michael Bosack, special adviser for government relations at the Yokosuka Council on Asia-Pacific Studies.

"Japan carries none of the historical or religious baggage of other potential mediators ... (and) has demonstrated its willingness to go its own way on Middle East policy," he said.

"These factors better position Abe for engagement with (Iran's Supreme Leader) Ayatollah Ali Khamenei and mean that Japanese-proposed options could allow hard-liners in Iran to entertain proposed off-ramps, without the potential fallout that could come from accepting 'Western' solutions."

Abe will meet Iranian President Hassan Rouhani and Khamenei on the June 12-14 trip. It will be the first time a Japanese prime minister has visited Iran since 1978.

Japanese Foreign Minister Taro Kono is expected to travel to Teheran to meet with his counterpart, Mohammad Javad Zarif, on Wednesday to pave the way for Abe's visit.

Against that backdrop, Japan is hoping to lower the temperature, officials said, with Abe winning Trump's blessing for the mediation trip when Trump visited Tokyo last month.

"We believe it is extremely important that, at the leadership level, we call on Iran as a major regional power to ease tension, to adhere to the nuclear agreement and to play a constructive role for the region's stability," Japan's Chief Cabinet Secretary Yoshihide Suga said ahead of the trip.

Iranian commentators said Abe could ferry messages between the two sides.

"Abe's visit comes right after meeting Trump in Japan. Therefore, the Americans are interested to use this channel," Ebrahim Rahimpour, a former Iranian deputy foreign minister, told Iran's Shargh daily ahead of the trip.

Iran will "announce our rights and stances and the other side can announce the messages that could be the Trump's message", he said.

But while Japan has long-standing ties with Teheran and warm relations with Washington, experts said Abe has little leverage with either side and mediation will be an uphill struggle.

The trip by the Japanese leader "faces substantial obstacles and is unlikely to bear fruit", said Tobias Harris, an analyst at Teneo consultancy group, in a note on the visit. "While Japan has good relationships with countries on both sides, these relationships do not necessarily translate into influence," he added.

'Shuttle diplomacy'?

Japan is not just the messenger. Its own interests are also at stake: Before US sanctions were reimposed, Tokyo imported around five percent of its oil from Iran and it would suffer from rising crude prices.

But analysts cautioned that expectations would stay low for now. "Japan has never played an active role in Middle Eastern problems," said Tetsuro Kato, political science professor at Tokyo's Waseda University. "I don't expect much in the way of results."

Bosack said it would be "unrealistic" to expect quick outcomes from the visit. "Right now, the focus is mitigating military conflict, which means Abe can employ shuttle diplomacy to keep communication going. That shuttle diplomacy alone may be enough to deescalate tensions," he said.

AFP/REUTERS/AP