The Navy will expand its air base on an East Sea island in a bid to ensure better protection of the nation's territorial waters surrounding the easternmost islets of Dokdo, a lawmaker said Wednesday.

According to Rep. Song Young-sun of the minor opposition Future Hope Alliance, the Navy recently inked a project to expand its base on Ulleung Island by about threefold to cover 5,040 square meters of land over the next two years.

Song said the Navy will also add a Lynx helicopter and an UH-60 Black Hawk to the base. The base currently operates a Lynx and a Coast Guard helicopter.

Sources said the measure is to strengthen defense of Dokdo.

Dokdo is about 90 kilometers from Ulleung and a Lynx can cover the distance in about half an hour, while a Black Hawk would be even faster, sources said.

According to sources, a Naval vessel from an east coast port needs more than four hours to reach Dokdo in an emergency, but a Japanese boat could reach the islets in about three hours, they said. (Yonhap News)