The Kremlin has tried to calm tensions in a feud between Trump and Medvedev that spiraled into nuclear threats.

Kremlin spokesman Dmitry Peskov emphasized that Russia does not view the latest movement as an "escalation" but claimed people were reacting emotionally on both sides.

Russia said on Monday that everyone should be "very, very careful" about nuclear rhetoric, responding to a statement by U.S. President Donald Trump that he had ordered a repositioning of U.S. nuclear submarines.