The chairman of South Korea’s main opposition Democratic Party Chairman has blasted Japan’s actions relative to its territorial claim over the Dokdo islets in the East Sea.

Sohn Hak-kyu said Wednesday at a Supreme Council meeting that the Japanese Diet and government are attempting to pillage South Korea’s sovereignty over the islets. Sohn said the Dokdo islets have been, are, and will always be South Korean territory.

The DP chairman added that Japan must contribute to peace in East Asia and take responsibility for its invasions of the region in the first half of the 20th Century.

On Monday, lawmakers from Japan’s Liberal Democratic Party attempted to visit Ulleung Island located near the Dokdo islets. And on Tuesday, the Japanese government claimed the islets as Japanese territory in its defense white paper for the seventh consecutive year.