Japan faces a dilemma over how to respond to the crisis in Ukraine following the vote Sunday by residents of Crimea, a majority of whom are ethnic Russians, in favor of seceding and joining Russia.

While Japan has been urging Russia to respect the sovereignty and territorial integrity of Ukraine, it is unclear whether Tokyo will join the United States and the European Union in imposing sanctions on Moscow, as doing so would affect negotiations involving the four Russian-held, Japanese-claimed islands off Hokkaido.

The administration of Prime Minister Shinzo Abe has been eager to improve relations with Russia, as exemplified by his participation in the opening ceremony of the Sochi Winter Olympics in February despite the absence of U.S. and European leaders in protest of Moscow's handling of human rights issues.