Indonesia has said Washington's occupation of Iraq had not met objectives and was in danger of becoming a debacle.
Foreign Minister Hassan Wirajuda also said the war in Iraq served as a wake-up call for Southeast Asia to get its own house to prevent similar events in the region.
"It is possible the forces of the old regime in Iraq, aided by foreign fighters infiltrated into the country, will continue to wage a prolonged guerrilla campaign," said Mr Wirajuda today.
"There is the dreadful prospect of the Balkanisation of Iraq with boundaries drawn on ethnic and sectarian lines," he also said in a speech to a security conference. "The various rival factions in Iraq today could be sucked by that power vacuum into a new and terrible round of internecine violence - a civil war."
He said that those developments would pose a threat to the Middle East, and the situation had heightened the grievances in the Muslim world and damaged the United Nations. If the various trends continue, "that would make the war in Iraq a debacle to the cause of security and peace".
The United States has tried hard to make strategically located and 80-per cent Muslim Indonesia an ally in Washington's war on terrorism.
It has had some success in getting the world's fourth-most populous country on board in regional efforts, but both the intervention in Afghanistan and the invasion of Iraq has brought widespread Indonesian criticism.