Saudi Arabia, with U.S. assistance, is pushing aside years of rancor with its neighbor Iraq and mounting a broad effort to win Baghdad’s allegiance and dilute Iran’s influence over the pivotal U.S. ally.

Saudi authorities are courting Iraq’s Shiite leaders, expanding the kingdom’s diplomatic presence, opening direct flights and reopening crossings closed for decades on the heavily fortified, 600-mile border.

“We share historical, cultural and social links with Iraq,” Thamer al-Sabhan, minister of state for Gulf affairs said after stopping at the newly reopened Arar border crossing. “If anything, I think we should be moving even faster.”

The shift provides a political and economic lift to the Iraqi government as it drives Islamic State from the country and moves to rebuild.