The quake struck at 7:20 a.m. Saturday (2220 GMT Friday) just off the coast of Hokkaido, the northernmost of Japan's four main islands, the agency said.
The temblor rattled areas along Hokkaido's southern coastline as well as the northern reaches of Japan's main island of Honshu, but there were no immediate reports of damages or injuries.
Japan is one of the world's most earthquake-prone countries because it sits atop four tectonic plates.
Putin's official spokesman Dmitry Peskov commented on remarks in the US media about failures in launching nuclear-capable missiles in Russia
More than 5.8 million people voted for Nicholas Maduro at the presidential election in Venezuela. This is more than a quarter of registered voters. Why did those people vote for the man, who, as Western media write, took Venezuela to the brink of collapse?
It has long been understood that the West has been trying to subject Russian borders to total control. We have not seen such activity even during the Cold War