Haiti and the donors have yet to agree to a plan on how that money will be disbursed, but a major element is a request for $350 million for the government for the rest of this year.

“The budget support is fundamental,” said Robert B. Zoellick, the president of the World Bank, noting that many donors had resisted this kind of assistance in the past out of concerns over corruption and the government’s ability to carry out projects.

Major international donors and the Haitian government itself have said that the rebuilding presented an opportunity to try to break the traditional cycle in which donors finance projects through nongovernmental organizations, bypassing the government.

Too many donors decide what Haiti needs and then find someone to make it happen, Haitian officials said. “In the end, the government has nothing to do with it,” said Gabriel Verret, a senior economic adviser to Mr. Préval. “That is the frustration.”

To ensure that the government gets to play a role, there are plans to create an interim reconstruction commission, with both donors and the Haitian government signing off on projects and expenditures. The government said Tuesday that the interim commission would be led by Mr. Préval and former President Bill Clinton.

(There has been a certain amount of grumbling around the United Nations about tight control by the State Department over the donor conference, with a senior European diplomat calling it “The Bill and Hillary Show.”)

United Nations diplomats said that in private the Obama administration and Haitian officials were still wrangling over the degree of involvement of Haitian government ministries in the reconstruction.

“Préval has been saying, ‘Wait, why should we build this parallel structure here,’ ” said a United Nations diplomat, who spoke on the condition of anonymity because of the delicate nature of the discussions. He said that the United States was pushing for the commission as a quicker, faster way to rebuild. In January, the United States offered to meet the payroll of the Haitian police, but insisted on issuing the checks. After the Haitian government realized that its officers would know they were being paid by the United States, it declined the offer and found the money elsewhere, diplomats said.