Russia's ambassador to Japan has reacted sharply to President Vladimir Putin not being invited to the annual ceremony marking the US atomic bombing of Hiroshima.

Mikhail Galuzin made the protest on Wednesday on the Twitter account of the Russian Embassy in Japan.

Hiroshima City had planned to invite Putin to the August 6 ceremony as it did in the past.

But after consulting with the central government, the city decided not to do so, explaining that the invitation could cause misunderstanding over Japan's stance on Russia's invasion of Ukraine.

Galuzin said, "Such an ignoble action is yet another proof that the leaders of the self-proclaimed anti-nuclear movement once again turned their backs on the memory of tens of thousands of their fellow citizens who became innocent victims of the USA's barbaric atomic bombing."

The ambassador also wrote in Russian on the Telegram messaging app, "The numerous bogus insinuations about the alleged possibility of Russia using nuclear weapons in Ukraine are being dishonestly spread."

Galuzin said Russia is seriously working toward nuclear nonproliferation.

He added, "Russia is not a rhetorical but a real leader promoting nuclear non-proliferation and the eventual elimination of nuclear weapons."