Anti-government protesters shout slogans during a rally to demand for the ouster of Yemen's President Ali Abdullah Saleh outside Sanaa University March 7, 2011. Yemen's opposition coalition vowed on Monday to escalate protests that have swept the country demanding the resignation of President Ali Abdullah Saleh, after he rejected a plan that would have him step down in 2011. REUTERS/Khaled Abdullah (YEMEN - Tags: POLITICS CIVIL UNREST)