South Korea Rarely Sells U.S. Dollars to Intervene in FX Market, Korean Won Hits Nine-Month High
Claire Weston
South Korea's FX authorities sold dollars on July 31 in a rare direct intervention, pushing the won up roughly 2% to a nine-month high of 1,418.0; markets suspect coordinated action with Japan, but staying power remains unproven.
What did South Korea do?
Citing informed market sources, Reuters reported that South Korea's FX authorities sold dollars and bought won on July 31 — a rare direct intervention.
The won rose to 1,418.0 per dollar, up about 2% on the day and its strongest level in nine months.
In plain terms = the central bank stepped onto the trading floor, dumped dollars, and muscled the won's price higher.
How far had the won fallen?
The won hit 1,561.50 last month — a 17-year low.
It has since rebounded more than 8% in July, on track for its largest monthly gain since March 2009.
This means → in a single month the won swung from an extreme trough to a policy-driven snapback — a violent round trip.
Why do markets suspect a Korea-Japan joint move?
On the same day, Japan's government bought yen and sold dollars in New York; the yen had previously slid to a nearly 40-year low.
South Korea's vice finance minister said publicly on July 2 that Seoul was in close communication with Japan and other key allies on FX matters.
Japan's top currency diplomat said on July 7 that Tokyo was in close contact with Seoul's FX officials, noting the two countries' financial markets "sometimes move in similar patterns."
This reflects a level of public coordination that, combined with same-day, same-direction action, left markets almost certain the two were acting in concert.
Can this intervention last?
South Korea's finance ministry FX officials declined to comment on the intervention — neither confirming nor denying.
In plain terms = official silence is itself part of the playbook — it keeps the market guessing.
Whether Seoul and Tokyo have formed a substantive joint-intervention mechanism, and whether the won can hold these levels, still depends on how rates move from here.
Content is for reference only, not financial advice.