President Vladimir Putin warned on Thursday that Russian gas supplies to Europe could be disrupted if Moscow cuts the flow to Ukraine over unpaid bills, drawing a U.S. accusation that it is using energy “as a tool of coercion”. In a letter to the leaders of 18 European countries, Putin made clear that his patience would run out over Kiev’s $2.2 billion gas debt to Russia unless a solution could be brokered urgently. Russia has nearly doubled the gas price it charges Ukraine, whose economy is in crisis, since pro-Moscow President Viktor Yanukovich was overthrown two months ago. Russia then annexed the Ukrainian region of Crimea, provoking the biggest confrontation with the West since the Cold War. Putin said Russian exporter Gazprom would demand advance payment for gas supplies to Ukraine and “in the event of further violation of the conditions of payment will completely or […]