Japan urged Russia on Monday not to annex Crimea and to protect the sovereignty and territorial integrity of Ukraine, saying the region's weekend referendum was "illegal" despite an overwhelming majority vote in favor of joining Russia.
"The referendum is not legally effective, and Japan does not accept the outcome," Chief Cabinet Secretary Yoshihide Suga told reporters, arguing the event "goes against Ukraine's Constitution which stipulates that any potential change to its territory should be put to a national vote."
"We will strongly urge Russia to abide fully by international law, respect the sovereignty and territorial integration of Ukraine, and not to annex Crimea," he said as Tokyo's top spokesman.
More than 95 percent of voters in the largely ethnic Russian region in southern Ukraine favored seceding from Ukraine and joining Russia in Sunday's referendum.
Senior Japanese government officials also said Tokyo will continue to work with other Group of Seven countries in handling the crisis in Ukraine.
Japan has found itself in limbo between the West and Russia since the crisis emerged, given that Prime Minister Shinzo Abe has met Russian President Vladimir Putin five times over the past year to build a closer personal relationship.
Tokyo and Moscow are locked in a territorial dispute over Russian-held islands off Hokkaido, called the Northern Territories in Japan and the Southern Krils in Russia, but Abe has been making it a priority to resolve the issue.
Foreign Minister Fumio Kishida did not clarify whether Tokyo will slap sanctions on Russia, telling reporters separately that Japan will need to see how Russia and other countries concerned will react to Sunday's vote.
"We want to respond appropriately after hearing the debates in related parties such as the European Union, Russia's response and the situation in Ukraine," Kishida said.