Russian President Vladimir Putin visited the far-eastern Kuril Islands for the first time on Thursday, prompting a “strong” protest by Japan which also claims the territory. Russian-Japanese relations have long been dogged by tensions over the contested islands, known in Japan as the Northern Territories and seized by the Soviet Union in 1945. The Kremlin posted a video of Putin in the Kuril Islands, with Russian media saying he visited a fish-processing plant where he was given caviar. Putin...