"Strong partnerships between the United States and allies and friends in the Asia Pacific region have been and remain pillars of security and prosperity in the region," he told a symposium in Washington.
"The world depends upon the stability and growth that together we can generate."
Powell specifically thanked the Philippines for giving diplomatic support, Australia for deploying 2,000 troops in Iraq, South Korea and Japan for providing medical and financial support.
He said the coalition effort is "committed to helping the liberated Iraqi people, help them achieve a stable and united country under a representative government that will use Iraq’s great natural human talent and its oil wealth to benefit all its citizens."
"The future of Iraq, finally, will be in the hands of its own people," he said.
The sight of Iraqi Shiites openly celebrating their religious holiday in Karbala for the first time since the fall of the Saddam Hussein dictatorship was "wonderful," he added. "It is a new day in Iraq."
President Arroyo is Washington’s most vocal ally in Asia. She is scheduled to visit the United States later this month. Her visit was originally scheduled on April 2 but she had to postpone it because of the war in Iraq, which began on March 20.
Mrs. Arroyo ran into domestic opposition for supporting US calls for Iraq to rid its arsenal of chemical and biological weapons that Washington accused Baghdad of secretly possessing in violation of international agreements.
She said Saddam Hussein had to be removed before he could provide terrorist groups that share his hatred of the United States with biological and chemical weapons.
The Philippines was enlisted in a US coalition of countries supporting the invasion shortly after the war began.