Russian President Vladimir Putin on Wednesday warned that Western arms deliveries to Ukraine were "a very dangerous step", especially if donors are "controlling" use of the weapons.

"Delivering arms to a warzone is always bad. Even more so if those who are delivering are not just delivering weapons but also controlling them. This is a very serious and very dangerous step," Putin told reporters.

Several countries, including Germany and the United States, have in recent weeks given the green light for Ukraine to use Western-supplied weapons to strike targets inside Russia in response to a new offensive launched by Moscow in northeast Ukraine last month.

Putin singled out Germany, saying that when the first German-supplied tanks "appeared on Ukrainian soil, it provoked a moral and ethical shock in Russia" because of the legacy of World War II.

Referring to German authorities, he said: "When they say that there will be more missiles which will hit targets on Russian territory, this definitively destroys Russian-German relations."

Putin repeated that his country "did not start the war against Ukraine", instead blaming a pro-Western revolution in 2014 which was followed by Russia's annexation of Crimea and a Moscow-backed separatist rebellion in the east of the country.

"Everyone thinks that Russia started the war in Ukraine. I would like to emphasise that nobody in the West, in Europe, wants to remember how this tragedy started," Putin said.