A power struggle in Iraq between the Shiite cleric Moqtada al-Sadr and rivals aligned with Iran is testing Tehran's ability to stave off a conflict that could damage its interests and further destabilize the oil-rich country.
With Sadr supporters camped out in parliament and his opponents protesting in the streets, the tussle over a new government has put fresh strain on a political system that has been buffeted by crises since US-led forces toppled Saddam Hussein two decades ago.
