An influential Saudi prince harshly criticized the Obama administration on Sunday for what he called indecision and a loss of credibility with allies in the Middle East. He said that American efforts to secure a peace deal between Israelis and Palestinians would founder without a clear commitment from President Obama. The Saudis have been particularly shaken by Obama’s refusal to intervene forcefully in the Syrian civil war, especially his decision not to punish President Bashar al-Assad of Syria with military strikes even after evidence emerged that Assad’s government used chemical weapons on its own citizens. The temporary agreement between the world powers and Iran over Iran’s nuclear program has caused more tensions between the United States and the Saudis.