South Korea said Tuesday that it will deploy a 5,000-ton patrol vessel to the Seoul-controlled rock outcropping of Ieodo, which has been the subject of a territorial dispute with China.

The newly built vessel will start patrolling the reef in April, according to an annual policy briefing by the Ministry of Public Safety and Security to President Park Geun-hye.

The move comes as China has repeatedly laid claim to Ieodo, which lies within the overlapping exclusive economic zones of the two countries.

Although international maritime law stipulates that a submerged rock cannot be claimed as territory by any country, South Korea effectively controls Ieodo, which is closer to it than any other country.

Also, the ministry said it plans to deploy an airplane to Yangyang, an eastern coastal city, as part of efforts to swiftly deal with emergencies around the easternmost islets of Dokdo.

The CN-235 fixed-wing airplane can fly for up to seven hours at a speed of 400 kilometers per hour and is fitted with a top-class scan radar, thermal equipment, flares and equipment for dropping lifeboats.

Dokdo has long been a key source of tension between South Korea and Japan as Tokyo repeatedly lays territorial claims over the rocky South Korean islets.

South Korea keeps a small police detachment on the islets, effectively controlling them. (Yonhap)