President Vladimir Putin warned the West on Wednesday Russia was technically ready for nuclear war and that if the US sent troops to Ukraine, it would be considered a significant escalation of the conflict.
Putin, speaking just days before a 15 March election which is certain to give him another six years in power, said the nuclear war scenario was not "rushing" up and he saw no need for the use of nuclear weapons in Ukraine.
"From a military-technical point of view, we are, of course, ready," Putin, 71, told Rossiya-1 television and news agency RIA in response to a question about whether the country was ready for a nuclear war.
Putin said that the US understood that if it deployed American troops on Russian territory - or to Ukraine - Russia would treat the move as an intervention.
"In the US, there are enough specialists in the field of Russian-American relations and the field of strategic restraint," said Putin, the ultimate decision-maker in the world's biggest nuclear power.
"Therefore, I don't think that here everything is rushing to it (nuclear confrontation), but we are ready for this," he said.
Putin's nuclear warning came alongside another offer for talks on Ukraine as part of a new post-Cold War demarcation of European security. The US says Putin is not ready for serious talks over Ukraine.
The war in Ukraine has triggered the deepest crisis in Russia's relations with the West since the 1962 Cuban Missile Crisis and Putin has warned several times the West risks provoking a nuclear war if it sends troops to fight in Ukraine.
Putin sent tens of thousands of troops into Ukraine in February 2022, triggering full-scale war after eight years of conflict in eastern Ukraine between Ukrainian forces on one side and pro-Russian Ukrainians and Russian proxies on the other.