South Korea on Monday established formal diplomatic relations with the Pacific island nation of Niue on the sidelines of Seoul's inaugural summit with 18 countries in the region.

A signing ceremony for the forging of diplomatic ties was held at Seoul's foreign ministry attended by Foreign Minister Park Jin and Dalton Tagelagi, the premiere of Niue who also doubles as the country's top diplomat.

According to the ministry, the small island nation with a population of some 1,600 is not a formal member of the United Nations, but is an active member of UNESCO and the World Health Organization.

The ceremony was held on the occasion of the two-day summit between South Korea and members of the Pacific Islands Forum to be held from Monday in Seoul.

Among the PIF members, Niue was the only country that had not established formal diplomatic relations with South Korea.

Niue became the 192nd country to establish diplomatic relations with South Korea. There are only three countries left in the world which Seoul has not established diplomatic relations with -- Kosovo, Syria and Cuba. (Yonhap)