President Donald Trump and Dmitri Medvedev, the former president of Russia and current deputy chairman of Russia’s Security Council, exchanged increasingly hostile messages this week that culminated in veiled nuclear threats from Moscow — marking a dangerous rhetorical turn amid rising tensions over Ukraine.[time-brightcove not-tgx=”true”]In a post early Thursday on Truth Social, Trump warned Medvedev to “watch his words,” calling him a “failed former President of Russia” and saying he was “entering very dangerous territory.” The warning came in response to Medvedev’s rejection of Trump’s recently tightened deadline for Russia to secure a peace deal in Ukraine.Hours later, Medvedev responded in kind, invoking the “Dead Hand,” a Cold War–era Soviet nuclear command system allegedly designed to trigger automatic retaliation if Moscow were struck. “Let him remember his favorite movies about ‘The Walking Dead,’ as well as how dangerous the non-existent in nature ‘Dead Hand’ can be,” he said.Though never officially acknowledged by the Russian government, the existence of the Dead Hand system was confirmed in 2011 by a retired commander of Russia’s Strategic Missile Forces, who claimed it could be reactivated if needed.Observers suggest that Trump’s targeting of Medvedev — rather than Russian President Vladimir Putin — is intentional, as it allows the President to appear tough on Russia without closing the door on potential direct negotiations with his Russian counterpart over Ukraine.The exchange followed a warning from Senator Lindsey Graham, Republican of South Carolina and close Trump ally, who said Monday that those underestimating the president “will soon be sadly mistaken.” Graham’s remark came shortly after Trump reduced his previously announced deadline for Russia to reach a cease-fire in Ukraine — from 50 days to just 10–12 — or face sweeping “secondary tariffs.”“It’s not for you or Trump to dictate when to ‘get at the peace table,’” Medvedev replied, in one of several barbed posts throughout the week.Medvedev, long known for incendiary statements on social media, dismissed the ultimatum outright Monday. “Trump’s playing the ultimatum game with Russia…Each new ultimatum is a threat and a step towards war. Not between Russia and Ukraine, but with his own country. Don’t go down the Sleepy Joe road!” he wrote on X, using Trump’s derogatory nickname for former President Joe Biden.Trump, for his part, has repeatedly cast blame on Biden for the war in Ukraine. “This war has been going on for three years. It’s a war that would have never happened if I was president. It’s Biden’s war,” he told TIME magazine earlier this year.In the same Truth Social post Thursday, Trump also lashed out at India, criticizing its energy and defense ties with Moscow. “I don’t care what India does with Russia. They can take their dead economies down together, for all I care,” he wrote. Trump’s comments reflect a broader pressure campaign on countries that continue economic ties with Moscow more than three years into its full-scale invasion of Ukraine.While Putin has avoided direct comment on the new ultimatum, the Kremlin has said it is monitoring the situation. Medvedev, meanwhile, has taken the lead in publicly confronting Trump, despite holding a largely symbolic role in the Russian leadership.Medvedev, who served as president of Russia from 2008 to 2012 and as prime minister until 2020, has since refashioned himself as one of the most hardline voices within the Russian establishment. Once seen as a pro-Western liberal, he now routinely makes aggressive statements invoking nuclear conflict and civilizational war with the West — remarks that analysts say are almost certainly sanctioned by the Kremlin.