"We have had a good response," Annan told reporters. As of yesterday, "A total of half a billion in assistance has been pledged and received, as well as contributions in kind. More than 30 countries have stepped forward to help us help millions of individuals from around the world."

The amount includes $250 million from the World Bank while the rest is from individual countries, Annan said.

"This is an unprecedented global catastrophe, and it requires an unprecedented global response. Over the past few days, it has registered deeply in the consciousness and conscience of the world as we seek to grasp the speed, the force and magnitude with which it happened.

"But we must also remain committed for the longer term. We know that the impact will be felt for a long time to come."

As many as five million people were displaced by tsunamis that killed nearly 119,000 people in Asia, officials said.