South Korea staged an annual military exercise on and around its easternmost islets of Dokdo earlier this month, sources said Friday.

The drill, which took place on Dec. 4, involved the Navy and the Coast Guard and was held on a smaller scale than previous drills, given the coronavirus pandemic and other factors, according to the military and government sources.

The Air Force and the Marines did not take part in the drill this time, they added.

The defense ministry and the Navy refused to officially confirm details about the latest drill, citing policy.

South Korea launched the Dokdo drills in 1986. Since 2003, it has typically conducted the training twice a year, usually in June and December, to better fend off possible foreign infiltrations to the rocky outcroppings and the surrounding waters.

In June, the military staged this year's first drill, involving around eight vessels and five aircraft, including F-15K fighter jets. In December last year, it replaced the exercise with a CPX due to inclement weather.

The June exercise became known to the public belatedly as the authorities did not disclose details in an apparent move to avoid aggravating tensions with Japan.

Bilateral relations between Seoul and Tokyo have been at one of their lowest ebbs in recent years over historic and diplomatic issues that have spilled over to the economic and military realms.

Japan has repeatedly laid territorial claims to Dokdo, though South Korea has been in effective control of the islets with a small police detachment since its liberation from Japanese colonial rule in 1945. (Yonhap)