The yen weakened below ￥92 against the US dollar for the first time since 2010, dragging Asian currencies lower.
The yen slid against most of its major peers and lost 0.4 percent to ￥92.10 per US dollar at 8:15am in London.
The Bloomberg-JPMorgan Asia Dollar Index dropped as much as 0.3 percent to a two-month low.
Officials in countries from South Korea to Taiwan said this week they may take steps to limit the impact on their exports from the weakening yen.
“Major Asian economies are looking for ways, such as currency depreciation, to counter a sliding yen’s impact on competitiveness,” said Bruce Yam, a currency strategist at Sun Hung Kai Financial Ltd in Hong Kong.
The yen is heading for a 12th weekly decline against the US dollar, which would be the longest stretch of losses going back to 1971, according to data compiled by Bloomberg.
Japan’s currency slid 1 percent to ￥125.8 per euro yesterday.
The South Korean won capped its biggest weekly loss since May after the government proposed a tax on securities trading to curb speculative flows.
A global currency war seems to be breaking out as monetary easing in Japan drags the yen lower, Bank of Korea board member Ha Sung-keun said this week.
Taiwanese policymakers said they may enter the currency market.
The Asia Dollar Index, which tracks the region’s 10 most-active currencies excluding the yen, lost 0.3 percent for the week.