Major trading house Mitsui & Co. was overpaid 205 million yen by a government-funded body in relation to the construction of diesel power stations on Russian-held islands and it has not returned the money, Foreign Minister Yoriko Kawaguchi said Tuesday.

In a letter sent to Mitsui on April 30, the Cooperation Committee demanded Mitsui return by May 20 the money it received as consumption tax for government-funded projects to build facilities on the islands, according to the Foreign Ministry.

The 205 million yen comprises 102 million yen to cover consumption tax for a project on Kunashiri Island, 74 million yen on Shikotan Island and 29 million yen on Etorofu Island, the officials said.

However, it was unnecessary to pay consumption tax on the Russian-held islands because the territories are considered foreign under tariff laws, despite Japan's claim to them.