The Russian military said today it caught a US submarine in its far-east waters and drove it out with 'appropriate means' after the vessel ignored a Russian request to leave, Interfax news agency has reported. The encounter came as Russian President Vladimir Putin and US President Joe Biden held a high-stakes phone call, as a tense world watched and worried that a Russian invasion of Ukraine could begin as soon as Wednesday. Biden warned his Kremlin counterpart that the United States 'will respond decisively and impose swift and severe costs on Russia' should it invade Ukraine.