* Trump's unpredictability makes trade war a real risk - Shinohara
* Ex-IMF official warns Japan it will face U.S. pressure for FTA
* Says U.S. won't listen to Japan calls for multilateral approach
TOKYO, March 30 (Reuters) - Japan will have little choice but to enter into a bilateral trade deal with the United States similar to one President Donald Trump clinched with South Korea, a former top Japanese currency diplomat said.
Naoyuki Shinohara, who was also deputy managing director at the International Monetary Fund, said Washington will keep pushing for a bilateral free trade agreement (FTA) with Japan given Trump's "America First" agenda - and Tokyo's calls to use a multilateral framework will only buy it some time.
"The United States is only interested in a bilateral deal and probably won't listen to Japanese calls for a multilateral approach on trade," said Shinohara, who retains close contact with international financial diplomats.
"Japan will eventually have to enter FTA talks" and face U.S. pressure to open up its auto and farm markets, he told Reuters on Friday.
Global markets were shaken this month when Trump moved to impose tariffs on Chinese goods and Beijing threatened similar measures, stoking fears of a global trade war.
Shinohara said there was a small but real risk of a United States-China trade war, which could spiral out of control given Trump's unpredictability.
"A trade war is a worse-case scenario and doesn't make economic sense as both sides will lose. But once there's a war, it's hard to stop shooting. The possibility is small but not unthinkable," he said.
An escalating trade spat could spread, including to Japan, said Shinohara, currently a professor at a University of Tokyo research institute.
SIMILAR APPROACH SEEN
Japanese policymakers worry that Trump could use a similar approach to what he took with South Korea, which agreed on a trade pact with a side deal to deter competitive currency devaluation.
Shinohara, who coordinated Asian policies during his IMF stint, said there was a "pretty good chance" Washington will make similar demands to Japan - entering talks for a bilateral FTA, with a side deal on currencies.
Trump will use such talks to demand more U.S. access to Japan's auto and highly-protected agricultural markets, he added.
Japan and the United States remain at loggerheads on how to frame trade talks, with Tokyo pushing back against U.S. calls for negotiations on a bilateral FTA.
Deputy Prime Minister Taro Aso has ruled out opening up talks for a bilateral trade deal, stressing that this would do no good for Japan.
Trade will likely feature as a topic when Trump and Japanese Prime Minister Shinzo Abe hold a summit next month. (Reporting by Leika Kihara; Editing by Richard Borsuk)