Officials here have said no political and diplomatic consideration was behind the recent decision by South Korea and Japan not to extend their currency swap facility worth $3 billion, which is due to expire in early July. After the Bank of Korea announced it Monday, a Finance Ministry official said neither Seoul nor Tokyo had requested the extension as they had not seen the need to do so.

But the termination of the swap line appeared the latest testimony to the strained relations between the two neighboring countries, which have been involved in renewed disputes for months over territorial and historical issues. Japanese media said earlier this month that Tokyo would not extend the currency swap deal unless Seoul asked for an extension. And South Korean officials had no intention of making the request in a way that could give the impression of seeking favor from Japan. In October, a similar war of nerves led the two sides to terminate an agreement to expand their total swap arrangement to $70 billion from $13 billion.

It is undesirable that Seoul and Tokyo have repeatedly deviated from economic logic in handling currency swaps. Their failure to keep a mutually beneficial scheme from being ditched in a diplomatic rift shows the two sides are still not working to ease strained ties and build a broader partnership. Seoul’s closer relationship with Beijing and right-wing Japanese politicians’ attempts to play up their nationalistic agenda have complicated the work to forge mutual trust between South Korea and Japan.

Behind Seoul’s decision not to request the swap facility extension with Tokyo may be its plan to strengthen monetary cooperation with Beijing. Meanwhile, Japan’s nationalistic politicians appear to have wanted to use the matter as a way to score points by pressuring South Korea into a submissive position. They have tried to widen voter support by denying Japan’s wartime atrocities and hardening their stance on territorial disputes with South Korea and China.

Reflecting the mutual antipathy fanned by such political considerations, an international survey released last month showed only 19 percent of Japanese respondents rated South Korea’s influence in the world positively, while 21 percent of Koreans polled gave a positive rating to Japan’s role.

But few people in both South Korea and Japan would want to leave the rift between their countries like this forever. Enhanced ties between them will be essential to securing regional stability and prosperity hopefully in an eventual partnership with China.

South Korea may need to consider steps to ease the strained relationship with Japan rather than further alienating it after President Park Geun-hye’s visit to China this week. It is hoped that the foreign ministers of the two countries will follow the past practice and meet on the sidelines of a regional security forum to be held in Brunei early next month.