The humanitarian response to the 2004 Indian Ocean earthquake was prompted by one of the worst natural disasters of modern times. On 26 December 2004, the earthquake, which struck off the northwest coast of the Indonesian island of Sumatra, generated a tsunami that wreaked havoc along much of the rim of the Indian Ocean. Particularly hard-hit were the countries of Indonesia, Sri Lanka, and Thailand. About 230,000 people were killed, tens of thousands more were injured, and 100 million became homeless and displaced.
Asian expatriates, governments, humanitarian organisations and individuals around the world arrived, eager to offer aid and technical support. Such was the global scope of the disaster that the International Charter on Space and Major Disasters was activated in quick succession by the French Civil Protection Agency, the Indian space agency ISRO, and by UNOOSA on behalf of UNOPS, thus providing a wide variety of humanitarian satellite imagery to aid and rescue organisations. The World Bank initially estimated the amount of aid needed at US$5 billion. Although numerous countries provided funds for relief and assistance, the UN criticised both the US and Europe for providing inadequate resources. By 1 January 2005 over US$1.8 billion (£1bn) had been pledged.
In wake of the disaster, Australia, India, Japan and the United States formed a coalition to coordinate aid efforts to streamline immediate assistance. However, at the Jakarta Summit on 6 January 2005, the coalition transferred responsibilities to the United Nations.