U.S. Chief of Naval Operations Adm. John Richardson has called for constructive discussions between Japan and South Korea to improve relations, with a view toward promoting freedom of navigation, as the two countries continue to be at loggerheads over an alleged radar lock-on incident last month.

“We continue to encourage all parties to work together” in order to resolve differences, Richardson told media organizations Friday, referring to the relationship among the United States, South Korea and Japan.

He expressed hopes for dialogue that will put the three countries “in a unity of effort to promote freedom on the seas.”

Such dialogue should be held “to promote long-term healing and reconciliation” and “in an atmosphere of mutual trust so that we could have a long-term benefit,” he added.

Japan’s relations with South Korea are deteriorating following a string of events. Among them is an incident in which a South Korean destroyer allegedly directed a fire-control radar at a Japanese patrol plane in the Sea of Japan on Dec. 20, an act that Seoul denies.

On the situation in the Taiwan Strait, where China has been increasing pressure on Taiwan, Richardson said, “We remain opposed to any kind of unilateral action from either side of the strait that’d change the status quo.”

“We don’t see really any kind of limitation on whatever type of ships could pass those waters,” he said, indicating that a U.S. aircraft carrier could sail through the strait.