Locked in a war in Ukraine which Putin said Russia had no choice to launch to safeguard its own security, the Kremlin chief warned that cycles of escalation in international conflict could quickly lead to dangerous scenarios.
"We must realise that the moment when nothing can be changed any longer may come very quickly and unexpectedly for everyone. The logic of escalating, increasingly harsh retaliatory measures leads to a fatal point of no return," Putin told the Valdai Forum of international Russia experts in Moscow.
"At the heart of this escalation lie arrogance and overconfidence. This is a path to the brink of the abyss. All the more so today, when the arsenals of the world's leading powers contain weapons capable of destroying all life or, at the very least, reducing the Earth to a catastrophic state. Can we be certain that these weapons will never be used? Well, of course not. We must bear this in mind and avoid such an outcome."
Putin said Russia had no plans to attack any European country and wanted to coexist peacefully.
But he reiterated that Russia would resort to all weapons in its arsenal, including nuclear ones, if its most westerly territory - Kaliningrad, which is wedged between Poland and Lithuania - was threatened.
"If it comes to a direct attack on the Russian Federation - in this case, we are referring to Kaliningrad, and perhaps other territories as well - the question of the Russian Federation deploying all the weapons at our country's disposal will, of course, inevitably and immediately be on the agenda," Putin said.
"This is inevitable," he said.
Putin said Russia realised it would be facing "an enemy (NATO) twice our size".
"And we will have to make use of our competitive advantages in this struggle. Yes, of course, France and the UK are nuclear powers - we understand that perfectly well and are fully aware of it," he said.
"But no one else possesses the kind of weapons that Russia has today. That is our competitive advantage."
Putin, who said he was ready for a trilateral meeting with Chinese President Xi Jinping and US President Donald Trump if a proper agenda was worked out first, ruled out the idea of stopping Russian strikes on Ukrainian targets in the Black Sea area while conceding that Ukrainian strikes on oil refineries across Russia had cost Russia one per cent of its gross domestic product.
He said Russia was now responding to Ukraine in kind.
But while he cast allies help to Ukraine when it came to launching deep strikes inside Russia as a future threat, he said Russia was not planning to attack arms factories in Europe which supplied Ukraine "tomorrow".
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