Russia’s AS-31 deep-diving nuclear-powered submarine, popularly known as Losharik, is set to be tested in June or July. The nuclear submarine is set to return to duty, five years after it caught fire during “underwater research” off the coast of the Kola Peninsula. The spy submarine, whose NATO reporting name is “NORSUB-5”, has been undergoing repairs and refurbishment since 2019 when a fire on board killed 14 sailors. Since the full-scale invasion of Ukraine in 2022, President Putin has made beefing up the country’s military capabilities a priority.