UNITED NATIONS — Secretary-General Ban Ki-Moon and U.S. Secretary of State Hillary Rodham Clinton appealed to the world’s nations Wednesday to donate $3.8 billion to start rebuilding earthquake-ravaged Haiti — and the world responded even more generously.

In the first minutes of a day-long donors conference, the United States and the European Union pledged more than two-thirds of the requested amount.

late afternoon, a U.N. tally showed that nations and organizations had pledged nearly $5.1 billion for the next 18 months.

It was not immediately clear if all those pledges were new money, as some delegates appeared to be describing already existing aid projects.

“the end of this day I am confident we will truly have helped Haiti along the road to a new and better future,” Ban said in his opening address.

Haiti’s President Rene Preval asked donors to focus on education and help the country’s 9 million people provide for their own future.

“Let us dream of a new Haiti whose fate lies in a new project for a society without exclusion, which has overcome hunger, in which all have access to secure shelter (and their) health needs provided,” he told diplomats and ministers from more than 130 countries.

Clinton announced the United States’ pledge of $1.15 billion over the next two years. Catherine Ashton, the European Union foreign affairs chief, then announced the EU’s pledge of 1.235 billion euros, equivalent to over $1.6 billion.

The $3.8 billion Haiti is seeking for the next 18 months is just the initial part of an $11.5 billion package Preval’s administration wants to rebuild schools, hospitals, courthouses and neighborhoods destroyed when the magnitude-7 earthquake pulverized its capital on Jan. 12.

Haiti’s government has detailed its plans for the money in a 55-page rebuilding plan that lays out the interim reconstruction committee. It includes requests for $350 million in direct budget support to the government, which Edmond Mulet, the top resident U.N. envoy there, said is crucial for the country’s progress.

“We need Haiti to succeed,” Clinton said. “What happens there has repercussions far beyond its borders.”