Japan's top FX diplomat Mimura issued his clearest warning yet to speculators on Thursday: "This is my final warning before action."

Finance Minister Katayama added that the time for "bold steps is now nearing," language that typically signals imminent currency intervention.

This comes as the yen weakened beyond 160.7 per US Dollar earlier on Thursday, approaching levels that triggered multiple rounds of intervention in 2024, before firming to 159.3 following the warning.

Japan has intervened in currency markets 6 times since 2022, spending ~$100 billion in 2024 alone to prop up the yen, with individual interventions ranging from ¥729.6 billion to ¥5.92 trillion.

Earlier this week, both the Bank of Japan and the Fed held interest rates steady this week, keeping the wide rate differential between the 2 countries intact and continuing to pressure the yen.

Japan's top currency official issued what he called a "final advisory" to speculators, while Finance Minister Katayama warned that the time for "bold steps" is now nearing — language that typically signals imminent intervention.

Higher oil prices driven by the Iran war are adding further pressure, as Japan's heavy reliance on Middle Eastern oil raises the risk of a deteriorating trade balance.

With the BoJ signaling it needs more time before hiking rates, intervention may be the only near-term tool available to halt the yen's decline.

The yen continues to weaken, and Japan is running out of words.