The move follows comments by former Russian president Dmitry Medvedev reminding President Donald Trump that Moscow possesses nuclear strike capabilities.

President Donald Trump issued a rare threat of nuclear escalation on Friday, saying he had ordered two nuclear submarines to be strategically positioned near Russia in response to what he said were aggressive remarks by Dmitry Medvedev,

P resident Donald Trump said on Friday he's ordered two nuclear submarines to move in the "appropriate regions" in response to what he called "highly provocative statements" from the deputy chair of Russia's security council, Dmitry Medvedev.