Japan's automakers are ramping up home production while expanding U.S. output to counter a 15% tariff on Japan-built cars, expected to cost the industry 1.9 trillion yen ($12.9 billion) this fiscal year, Nikkei reported Wednesday.

Mazda (TYO:7261), Toyota (TYO:7203) and Honda (TYO:7267) are cutting costs, redirecting exports and pushing domestic demand, while seeking government support to protect supply chains, according to the report.

Tariffs have already driven steep regional sentiment drops and heavy losses - Toyota and Honda each face a 450 billion yen annual hit, and Mazda 70 billion yen, the report said.

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