The government Tuesday defended its decision to impose tighter controls on technology-related exports to South Korea, amid Seoul's failure to come up with a "satisfactory" solution to the wartime labor dispute.

Chief Cabinet Secretary Yoshihide Suga said the measure will be imposed for national security reasons, not as retaliation, and claimed that it does not go against the spirit of free trade or World Trade Organization rules.

South Korea "did not show a satisfactory solution over the issue of former workers on the Korean Peninsula before the Group of 20 summit (last week) and we cannot help but say the relationship of trust has been severely damaged," Suga said at a news conference.