Japan will place additional sanctions on Russia after the Group of Seven (G7) summit the country hosted last week agreed to step up measures to punish Moscow's invasion of Ukraine, Chief Cabinet Secretary Hirokazu Matsuno said on Friday.

Matsuno, Tokyo's top government spokesperson, also condemned Russia's move on Thursday to deploy tactical nuclear weapons in Belarus, saying it would further intensify situations around the invasion of Ukraine.

"As the only country to have suffered atomic bombings during wartime, Japan never accepts Russia's nuclear menace, let alone its use," Matsuno said during a regular news conference.

The leaders of G7 nations, including the United States, Britain, Germany, France, Italy and Canada, last week showed their resolve to support Ukraine with additional military aid and sanctions on Russia, at the annual summit held in Hiroshima, the world's first atomic-bombed city.

In a coordinated action with the G7, Japan will freeze assets of 78 groups and 17 individuals, including army officers, in Russia and ban exports to 80 Russian entities such as military-affiliated research labs, according to a Foreign Ministry statement on Friday.

Japan will also ban providing construction and engineering services to Russia, although the details of the measure will be announced at a later date, a trade ministry statement said.