Russia's intervention in Ukraine has put NATO allies in eastern Europe on edge and triggered a series of military moves by the NATO alliance, including an acceleration of exercises and the creation of a NATO rapid response force, Censor.NET reports citing Reuters.
Carter, who will view components of that NATO force later on Monday, said the alliance would keep the door open to an improved relationship with Russia but said flatly: "It's up to the Kremlin to decide."
"We do not seek a cold, let alone a hot war with Russia. We do not seek to make Russia an enemy," Carter said. "But make no mistake: we will defend our allies, the rules-based international order, and the positive future it affords us all."
Carter said on Sunday the United States and NATO were preparing militarily for the prospect that their rift with Russia could even outlast President Vladimir Putin.
"The United States will not let Russia drag us back to the past," he stated.