Fed should proceed 'cautiously' given global risks, Yellen says

By Jonathan Spicer and Jennifer Ablan NEW YORK (Reuters) - Federal Reserve Chair Janet Yellen said on Tuesday the U.S. central bank should proceed "cautiously" as it looks to raise interest rates again, because inflation has not yet proven durable against the backdrop of looming global risks to the U.S economy. In her first comments since the Fed decided to hold rates steady two weeks ago, Yellen again sounded cautious tones about threats to the recovery of the world's biggest economy, appearing