“We remain very concerned about the situation and will continue to monitor it closely,” Austin quoted TASS as saying.
He stressed that the United States is "committed to protecting the sovereign territory of Ukraine."
According to him, Washington is considering various ways to defend Ukraine.
Earlier, The New York Times, citing American and European sources, reported that the United States had warned its allies in Europe about the risk of a "Russian invasion" of Ukraine.
This was also reported by the CBS television channel, according to which representatives of the American intelligence services believe that the likelihood of Russia's "invasion" of Ukraine "grows as the snap gets cold."
The official representative of the Russian Foreign Ministry, Maria Zakharova, commented on the publications of the Western media about the concentration of Russian troops on the border with Ukraine, allegedly to prepare for an invasion of the territory of a neighboring state.
Dmitry Peskov, a spokesman for the Russian president, said Russia was not going to attack anyone.