By Phil Stewart and Idrees Ali
WASHINGTON - Russia has not yet notified the United States about exercises of its nuclear forces that Washington expects Moscow to carry out soon, a senior U.S. military official said on Monday.
The United States says Russia will likely carry out test launches of missiles during its annual "Grom" exercises of its strategic nuclear forces, perhaps in just days.
Under the New START Treaty, Russia is obliged to provide advance notification of such missile launches, U.S. officials say. That has yet to come, the U.S. military official said, speaking on condition of anonymity.
"No, we have not received any type of official notification," the military official told reporters. The drills present another challenge to the United States and its allies as Russian President Vladimir Putin openly threatens to use nuclear weapons to defend Russia in its unraveling invasion of Ukraine.
Still, Western officials have expressed confidence in their ability to discern the difference between a Russian drill and any move by Putin to make good on his threats.
Russia attacked Ukrainian cities with drones during morning rush hour on Monday, killing at least four people in an apartment building in Kyiv, in the latest wave of what Ukraine and the West say are deliberate strikes on civilian targets.
The U.S. military official condemned the Russian strikes, saying they appeared designed to terrorize Ukraine's civilian population.
"We assess that Russia has deliberately struck civilian infrastructure and non-military targets for the purpose of needlessly harming civilians and attempting to instill terror among Ukraine's population," the military official said, speaking on condition of anonymity.
The White House said the United States will hold Russia accountable for "war crimes," a term used by America's top general in Brussels last week.
Russia denies targeting civilians in what it calls its "special military operation" in Ukraine, launched on Feb. 24 and including the biggest annexation of territory in Europe since World War Two.
The U.S. military official said history showed that air campaigns that try to psychologically cripple a population with such tactics will backfire.
"It doesn't work," the official said, adding that if anything it has increased the resolve of the Ukrainians.