Saudi Arabia has sidelined its veteran intelligence chief, Prince Bandar Bin Sultan, as leader of the kingdom’s efforts to arm and fund Syrian rebels, replacing him with another prince well-regarded by U.S. officials for his successes fighting al Qaeda, Saudi royal advisers said this week.

The change holds promise for a return to smoother relations with the U.S., and may augur a stronger Saudi effort against militants aligned with al Qaeda who have flocked to opposition-held Syrian territory during that country’s three-year war, current and former U.S. officials said.

Prince Bandar, an experienced but at times mercurial ex-diplomat and intelligence chief, presided over Saudi Arabia’s Syria operations for the past two years with little success, as a rift opened up with the U.S. over how much to back rebels fighting Syrian President Bashar al-Assad.