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

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.

The Kremlin warned Monday against “nuclear rhetoric” after President Trump repositioned two nuclear submarines because of what he called “foolish and inflammatory statements” by former Russian president Dmitry Medvedev.