Former Russian president Dmitry Medvedev has become embroiled in a tense back-and-forth on social media that prompted U.S. President Donald Trump to announce he had ordered the re-positioning of two U.

“Putin uses Medvedev as a tool to express statements related to nuclear weapons, he doesn’t want to discredit his own good peacekeeper’s name,” Lieutenant-General Ihor Romanenko, former deputy head of the General Staff of the Ukrainian Armed Forces, said ironically.

President Donald Trump has reportedly hinted that his nuclear submarines are now "in the region of Russia" after he ordered them there following a comment made by former Russian President Dmitry Medvedev.