An Iraqi aviation official says authorities ordered a Damascus-bound Syrian plane transiting Iraqi airspace to land for inspection, but that no weapons were found onboard.

Nassir Bandar, Iraq's top civil aviation official, says inspectors checked the Airbus passenger plane traveling from Moscow on Sunday morning. It was the first time Iraq has reported inspecting a Syrian plane.

The United States has been pressuring Iraq to do more to ensure that its airspace and territory are not being used to ferry weapons to Syrian President Bashar Assad's embattled regime.

Baghdad has stepped up inspections of Iranian flights in recent days. Tehran is a major backer of Assad and also maintains friendly relations with the Shiite-led government Baghdad.