U.S. Ambassador to Korea Harry Harris on Monday tried to calm a naval spat between Korea and Japan in closed-door meetings with Defense Minister Jeong Kyeong-doo and Foreign Minister Kang Kyung-wha.

The U.S. seems to have grown alarmed at the escalating conflict between its two regional allies over Japanese spy planes buzzing Korean warships in the East Sea and taken on the role of mediator.

Harris made an unannounced visit to the Defense Ministry in Yongsan on Monday afternoon and spoke to Jeong for about an hour and 20 minutes.

The main point was to exchange views on cost-sharing for the upkeep of the U.S. Forces Korea, which the two sides have failed to agree on, but considerable time was apparently spent discussing the naval spat with Japan.

Jeong "explained how unreasonable Japan's claims are, while Ambassador Harris voiced concern over the conflict between the two countries," a ministry official said. Japan complains that a Korean destroyer last month locked its firing radar on an overflying Japanese plane but has since continued close flybys.

