The content originally appeared on: CNN (CNN)President Joe Biden told Ukrainian President Volodymyr Zelensky on Sunday that the US and its allies 'will respond decisively if Russia further invades Ukraine,' according to a readout of a call between the two leaders provided by the White House. The two spoke just a few days after Biden urged Russian President Vladimir Putin to ease an unremitting military crisis on Ukraine's border and before Russian and US officials are set to meet in […]