In northern Iraq, Kurds warn: "Beware the Arabs"

Just off the Mosul road that runs through the vivid green plains of Iraq's Nineveh Province, a Kurdish security officer - a peshmerga - checks our documents, though we are several miles outside Kurdistan Regional Government (KRG) borders. "Careful," he says, gesturing at the road ahead. "There are Arabs." The checkpoint, manned by Kurdish forces, is on the country's "trigger line", a 300-mile unofficial boundary between the areas run by the KRG and the Iraqi central government - a border that some fear will be the setting for the country's next civil war. The KRG claims that areas of northern Iraq with a large Kurdish population ought to be part of its jurisdiction, and says its peshmergas were invited across the official green line by US forces to help protect the local people. Arab nationalist parties accuse the KRG of occupying disputed land. The governance of these areas, particularly the oil-rich city of Kirkuk, is a focal point for post-election bargaining over the make-up of the ruling coalition. US forces have begun to play an important role in managing Arab-Kurd tensions, but they are scheduled to withdraw by the end of the year, leaving little time to cut a deal.