The Japanese currency fell 0.2% to 160.06 per greenback, extending losses this year to around 12%. The vast gap between interest rates in Japan and the US remains the fundamental reason for yen weakness and has kept pressure on the currency despite attempts to stem its slide.

“Rhetoric from the ministry of finance in recent days has signalled increased concern but not imminent intervention,” said Erik Nelson, macro strategist at Wells Fargo in London.

“We would likely need to see a clear break of 160 and an acceleration with bigger daily moves for the MOF to take action,” he said, adding that Japanese authorities may wait for the yen to slilde to 165 or above to enter the market.

The next big pain point for the yen — and a potential trigger for action from officials — may emerge from a readout on the Federal Reserve’s favored US inflation gauge on Friday, which is key to the outlook for US interest rates.

So far, officials in Tokyo have limited their response to verbal warnings this week. Finance minister Shunichi Suzuki said they are closely monitoring developments in the market and will take all possible measures as needed.

The country’s top currency official, Masato Kanda, warned on Monday that authorities stand ready to intervene, 24 hours a day, if necessary, while reiterating they were not targeting a specific level.

Japan spent a record ¥9.8 trillion (US$61.2 billion) in the period between April 26 and May 29 to prop up the yen after it fell to a 34-year low against the dollar, surpassing the total amount it used in 2022 to defend the currency, according to official data. Movements in the yen suggest this happened on April 29 and May 1.