Washington (AFP) – US Treasury Secretary Janet Yellen walked out of a meeting Wednesday of finance officials from the world’s richest countries along with several of her counterparts when Russian officials spoke, in protest against Moscow’s invasion of Ukraine, a source familiar with the event said. Moscow’s attack on its neighbor loomed over the meeting of G20 finance ministers and central bank governors, the first since President Vladimir Putin ordered the invasion in late February. British, French and Canadian officials joined the boycott, officials confirmed, underscoring the boiling tensi…