Japan will take all possible steps with a "strong sense of urgency" as currency moves should be stable and based on economic fundamentals, Finance Minister Shunichi Suzuki said Friday after the yen slipped past the key 150 mark against the U.S. dollar.

Asked whether Japan intervened on Thursday as the dollar briefly dipped from the upper 150 yen zone, a one-year high, Suzuki declined to comment.

The yen's decline reflects a widening interest rate differential between Japan and the United States.

The Bank of Japan has allowed 10-year Japanese government bond yields to rise more within its yield curve control program but remains committed to monetary easing, in stark contrast with the U.S. Federal Reserve which has aggressively raised interest rates to fight surging inflation.

"I have repeatedly said foreign exchange moves should be stable, reflecting fundamentals, and that excessive volatility is undesirable," Suzuki said at a press conference.

The weaker yen has inflated import costs for Japan, driving inflation higher and prompting the government to take a spate of measures to ease the pain on households. A fresh economic package will be formalized on Thursday, featuring subsidies to reduce fuel costs and tax cuts.

Suzuki has said the government does not have a specific dollar-yen level in mind when deciding to intervene, adding that it is focused on volatility.

Still, 150 yen to the dollar is seen as a psychologically important level, and thus a line of defense for Japanese authorities.

The yen's weakening also poses a challenge to the BOJ ahead of a two-day policy-setting meeting starting Monday. The central bank loosened its grip on 10-year yields in July to allow for more flexibility and address volatility in the currency market.

In the bond market, 10-year yields have been climbing toward the current upper limit of 1.0 percent set by the BOJ.

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