Russia's authorities should revive the old Cold War practice of training civilians on how to respond in the event of a large-scale nuclear attack, a senior government official said on Friday.
Speaking after a meeting of Russia's Security Council chaired by President Vladimir Putin, Dmitry Rogozin, the deputy prime minister in charge of the defense industry, said the United States was upsetting the nuclear balance by developing new weapons systems.
Russia had no choice but to react to the aggressive capabilities of the United States, he said.
"Measures for countering the aggressor could include those that concern Russia's strategic nuclear capability, that is reciprocal measures so that, God Forbid, no one gets a crazy idea in their head," Rogozin said.
There could be other measures "so that the population, if nonetheless they were subject to that kind of aggression, could avoid colossal losses. ... Civil defense should be recreated," he said.
During the Cold War, Soviet authorities built a system of bomb shelters in case of a nuclear attack, and school children were trained how to put on protective masks. Posters telling people how to respond hung in schools and workplaces.
Many Soviet citizens were skeptical that any of the precautions could save them if there was an attack, but the training, known as civil defense, was compulsory.
The practice was abandoned under the last Soviet leader Mikhail Gorbachev, who with U.S. leaders negotiated a program of nuclear arms cuts that eased tensions.
But under Putin, relations between Washington and Moscow have soured, with the two sides at loggerheads over the conflict in Ukraine, ways to end the crisis in Syria and human rights issues.
The Russian leader has spoken often of the United States' and its allies encroaching into eastern Europe and threatening Russia's national security.
At a forum in the southern Russian city of Sochi earlier this month, he said a missile shield planned by the US military was a direct threat to Russia's nuclear capability.
