Japan expressed regret Thursday after Russia signed into law a bill establishing a tariff-free zone on four Russian-held islands claimed by Japan.The Russian move came as Tokyo and Moscow have been discussing a plan to hold joint economic activities on the islands, called the Northern Territories in Japan and the Southern Kurils in Russia, without harming the legal stance of either country."It is not in line with Japan's position on the four islands or the aim of the joint economic activities the two sides have been discussing. It is deplorable," said Chief Cabinet Secretary Hirokazu Matsun…READ FULL ARTICLE