South Korean President Moon Jae-in on Thursday said ties with Japan should be improved for national security as well as economic development for the future.

"We do need to have a good relationship with Japan, but due to unfortunate history of the past, problems have constantly occurred, making the ties between the two countries uncomfortable," said Moon at a luncheon with experts.

Moon, however, added that he feels sorry at the same time to see Japan's use of history in its politics, which he said seems to be "exacerbating" the ongoing controversies.

Ties between Seoul and Tokyo have been bedeviled by issues arising from Japan's colonial rule of the Korean Peninsula between 1910 and 1945.

The two countries reached an agreement in 2015 aimed at settling the issue of "comfort women." The term is a euphemism used to refer to women who provided sex, including those who did so against their will, for Japanese troops before and during World War II. But a new government in Seoul has since revisited the deal, concluding it could not settle the long-standing issue as it failed to reflect the opinions of surviving victims.

Bilateral ties have been under added pressure since a string of court rulings in South Korea in favor of wartime forced laborers seeking compensation.

Japan claims that the compensation issue was completely settled by 1965 bilateral treaty signed by the two countries.