Japan says it is slapping sanctions on Russia in response to Moscow's intervention in Ukraine, Reuters reports.

Japanese Cabinet Secretary Yoshihide Suga said in Tokyo today that the government is freezing all talks with Russia on relaxing visa requirements and on all new negotiations on investment accords and new agreements on space and military activities.

Suga, who is the top government spokesman, also said, "We ask that Russia respect international law and respect the integrity of Ukraine and not move towards annexing Crimea."

He also stressed Japan declared the Crimean so-called referendum, held on March 16, illegitimate.

"The referendum is invalid, and Japan does not recognize its results"- Suga noted.