South Korea and Japan are drawing again on a financial arrangement that predates most of the diplomatic disputes which have periodically frozen it: a bilateral currency swap line between the Bank of Korea and the Bank of Japan, first signed in 2001 and revived in June 2023 after an eight-year lapse. The $10 billion facility, agreed in dollar terms, gives each central bank a standing channel to exchange currencies during periods of market stress. Its renewed relevance in 2026 comes as the Korean won trades near multi-year lows against the dollar.
The won has traded past 1,430 to the dollar through much of the year, and Japanese authorities have at times intervened in currency markets alongside their Korean counterparts to slow the slide, according to Nikkei Asia. Washington has declined to extend Seoul a dedicated dollar swap line of the kind it offered Argentina, leaving the Bank of Korea to lean more heavily on its existing regional network.
A line with a complicated history
The Korea-Japan swap traces back to the aftermath of the 1997-98 Asian financial crisis, when regional central banks built a web of bilateral agreements under the Chiang Mai Initiative to avoid relying solely on the International Monetary Fund during a currency crunch. The Seoul-Tokyo line expanded over the following decade, reaching tens of billions of dollars in capacity by the early 2010s.
It lapsed in 2015 amid a chill in bilateral relations tied to historical and territorial disputes, and stayed frozen for eight years even as trade and financial ties between the two economies continued largely uninterrupted. Finance officials from both countries restarted talks in 2023 as relations between Seoul and Tokyo thawed, and the two sides signed a revived agreement that June — this time denominated in dollars rather than in yen and won directly, according to Reuters and Bank of Japan records.
How the facility actually works
A currency swap line does not require either side to draw on it in order to be useful. Its value lies largely in the signal it sends: that the Bank of Korea has a pre-arranged channel to obtain dollars from the Bank of Japan, and vice versa, if short-term funding markets seize up. That reduces the odds that speculative pressure on the won turns into a self-fulfilling funding crisis.
The $10 billion cap is modest next to the Bank of Korea's broader swap network, which the central bank reports totalled roughly $150.6 billion as of the end of March 2026 across arrangements with China, several ASEAN members and Canada, among others. The Japan line's significance lies less in its size and more in restoring a bilateral channel between the region's second- and fourth-largest economies that had sat dormant for the better part of a decade.
One line among several
The Seoul-Tokyo arrangement sits inside a wider regional safety net. The Chiang Mai Initiative Multilateralisation, the ASEAN+3 pool that grew out of the same 1997-98 crisis response, now totals roughly $240 billion in committed swap capacity spread across thirteen member economies. Korea layers its own bilateral lines on top of that pool, including long-standing arrangements with China, Indonesia, Malaysia, Singapore, Australia and an unlimited swap with Canada.
Analysts tracking the region's currency markets point to a mix of factors behind the won's weakness this year: a wide gap between Korean and US policy rates, capital rotation into US technology equities, and the sensitivity of Korea's export-heavy economy to swings in the global semiconductor cycle. None of those pressures are new, but together they have kept the currency under sustained strain.
Reviewed, not automatic
Bank of Japan and Bank of Korea officials have continued periodic consultations since the 2023 revival, consistent with how the original 2001-2015 arrangement was managed — reviewed and renewed in stages rather than locked in permanently. Neither central bank has signalled that the current facility is at risk of lapsing.
The two sides agreed at the 2023 signing to continue regular finance-ministry talks, a schedule that has largely held since. Whether that consultative rhythm survives the next dip in bilateral relations is, going by the line's own history, an open question rather than a formality.
Japan has its own currency to watch
The yen has not been immune to the pressures weighing on the won. Japanese officials have intervened in currency markets on their own account at several points over the past two years, citing excessive volatility rather than defending a specific exchange-rate level, in line with the Bank of Japan's long-standing position that it targets stability rather than a fixed rate. That shared exposure to dollar strength is part of what has made renewed cooperation between the two central banks practical rather than purely symbolic.
Currency-market officials in both countries have also pointed to a broader pattern across Asia's export economies in 2026: sustained dollar demand tied to US rate policy, combined with slower-than-expected capital inflows into regional equity markets, has left several currencies beyond the won and the yen — including the Indonesian rupiah and the Philippine peso — under similar, if less pronounced, pressure. Regional finance ministries have discussed the pattern at recent ASEAN+3 meetings without announcing coordinated action beyond the existing network of bilateral and multilateral swap lines.