The Japanese government lodged a protest Tuesday with South Korea over a visit by a South Korean lawmaker to Takeshima, a group of islets in the Sea of Japan controlled by Seoul but claimed by Tokyo.

The visit Sunday to the islets called Dokdo in South Korea by the opposition lawmaker was timed for the 76th anniversary of Japan's surrender in World War II in 1945, which ended Tokyo's colonial rule of the Korean Peninsula from 1910.

Photo taken in April 2005 shows one of the South Korea-controlled Dokdo islets, known as Takeshima in Japan. (Getty/Kyodo)

The lawmaker made the visit despite Tokyo's request in advance not to do so, the Japanese Foreign Ministry said.

Takehiro Funakoshi, director general of the Japanese Foreign Ministry's Asian and Oceanian Affairs Bureau, protested to Kim Yong Gil, a minister at the South Korean Embassy in Tokyo, saying the islets are an "inherent part" of Japanese territory.

In Seoul, a senior official at the Japanese Embassy conveyed a similar message to a South Korean Foreign Ministry official.

The rocky outcrops have long been a source of tension between the two Asian neighbors. South Korea has been in effective control of them since the 1950s.

Earlier this month, Tokyo made a protest against Seoul for starting to stream images from the islets. South Korea said the service is aimed at increasing its people's interest in and affinity for the territory.