Wholesale prices in Japan surged 9.7 percent in September from a year earlier to their highest level ever, as a sharp fall in the yen inflated import prices for energy and raw materials, Bank of Japan data showed Thursday.

The increase in the prices of goods traded between companies was the second highest, following a record 9.8 percent rise in April, with the year-on-year figure remaining above 9 percent throughout 2022 as Russia's war against Ukraine and the yen's rapid weakening add to inflationary pressure.

The corporate goods price index reached 116.3 in September, its highest level since comparable data became available in 1960.

Wholesale inflation, which affects consumer prices with a lag, rose for the 19th straight month, threatening to hurt corporate profits. A growing number of Japanese firms have already been passing on higher costs.

Import prices soared 48.0 percent from a year earlier in yen terms. The Japanese currency has slumped to its lowest level in over two decades relative to the U.S. dollar, reflecting the widening interest rate differential between the two nations.

Export prices, meanwhile, rose at a slower pace of 20.1 percent.

More than half of the rise in import prices in September was due to the effect of the yen's depreciation, the BOJ data showed, making it more challenging for the central bank to stick to its ultraloose monetary policy.

Japan stepped into the foreign exchange market by buying the yen for dollars on Sept. 22, but its first such intervention since 1998 has failed to reverse the trend of yen weakness. It was trading within striking distance of 147 to the dollar.

Coal and petroleum product prices jumped 14.7 percent, while steel prices surged 26.1 percent. Electricity, city gas and water prices rose 38.8 percent.

The core consumer price index, excluding volatile fresh food items, has topped the Bank of Japan's 2 percent target in recent months, though the central bank is in no hurry to adjust its ultralow rate policy, viewing the recent inflation as unlikely to last.

The government is preparing a fresh economic package to soften the impact of higher prices on households and support the economy as economists expect the core CPI to top 3 percent this year.

Still, BOJ Governor Haruhiko Kuroda reiterated Wednesday that consumer inflation will slow in the next fiscal year to below 2 percent, justifying the central bank's unwavering policy stance.

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