International Monetary Fund chief Christine Lagarde welcomed a move by central banks to inject dollars into banks threatened by the eurozone debt crisis as "exactly what is needed." The European Central Bank, along with its US, Japanese, Swiss and British counterparts, announced earlier Thursday they would inject extra dollar liquidity into banks facing a shortage of American currency. "The path to recovery needs collective action by both political leaders and central banks. What we saw today was exactly what is needed," Lagarde said in a brief statement. "It shows central banks will do whatever it takes to restore stability."