Korea's Dokdo islets in East Sea (Getty Images) South Korea rebuffed Japan's protest over Korea's marine survey near Dokdo, saying Japan's objections were unacceptable.The Ministry of Foreign Affairs on Sunday reaffirmed that Dokdo is indisputably South Korea’s sovereign territory, historically, geographically and under international laws, rejecting Japan's complaints about Korea's recent survey conducted near the islets."Japan filed an issue with an activity that is legitimate under international and domestic laws," the ministry said. "Any unfair claim regarding Dokdo is unacceptable." It added that Japan's objections had been rejected through diplomatic channels.Japan's Foreign Ministry lodged a protest with the South Korean Embassy in Japan on Friday, saying that Korea's research vessel "Tamhae 3" was conducting marine research in what Japan claims to be its exclusive economic zone, which extends to the west of Dokdo. Japan also said that the survey was done without its prior consent.The Japanese Embassy in Korea raised the same complaint to Korea's Foreign Affairs Ministry on the same day.Japan has long claimed Korea's easternmost islets of Dokdo as its own territory and routinely protests when Korea conducts a marine survey in nearby waters. Korea has dismissed such protests.