The United Nations is urging South Korea and Japan to resolve an ongoing dispute over the name of the body of water between their two countries.

The U.N. Group of Experts on Geographical Names (UNGEGN) issued the call in a report adopted at the end of its 22nd meeting on Thursday.

It is the first time for the U.N to advise the two countries to make efforts to address the issue.

The naming of the body of water, called "East Sea" by Koreans, has been a constant source of dispute between Seoul and Tokyo.

It was first named the "Sea of Japan" by the International Hydrographic Organization in 1929 upon Tokyo's request - this at a time when Korea was still under Japanese colonial rule.

After Korea regained sovereignty from Japan, Seoul embarked on efforts to have the name "East Sea" recognized internationally. Japan has insisted the name remain "Sea of Japan."