Chief Cabinet Secretary Yoshihide Suga said on Monday that the voting lacked democratic legitimacy, and that Japan fears the referenda could further worsen the situation in Ukraine.
The Japanese government expressed its opposition Monday to referendums held the previous day in eastern Ukraine, early results of which showed pro-Russian voters favored sovereignty in a move that may escalate tensions in the country.

He expressed hope that Ukraine's presidential election scheduled for later this month will be held in a peaceful and democratic manner.

Moreover, the head of Japan's national security panel has urged Russia to pursue a peaceful and diplomatic solution to the crisis in Ukraine.
Chief of National Security Council secretariat Shotaro Yachi met Russian Security Council Secretary Nikolai Patrushev, a close aide to President Vladimir Putin, in Moscow a week ago.
Yachi explained Japan's stance that it will not overlook an attempt to change the status quo through the threat of force.
He informed Patrushev that Japan took additional sanctions against Russia in April in concert with other members of the Group of Seven major countries.
Yachi also explained that Prime Minister Shinzo Abe values dialogue with Russia and urged Russia to take positive steps for a peaceful and diplomatic resolution to the crisis in Ukraine.