TOKYO - Aid donors said on Monday they would pledge over $3 billion for rebuilding Afghanistan to ensure the war-ravaged land never again becomes a breeding ground for terrorism.

The offers from the European Union, Japan, Saudi Arabia, the United States and others poured in as delegates at a two-day conference in Tokyo grappled with the complexities of a process that aid experts say will require some $15 billion over 10 years.

"In order to eradicate terrorism, we must eliminate the conditions that allow terrorism to take root," said Japan's prime minister, Junichiro Koizumi, announcing his country's pledge of $500 million over two-and-a-half years.

Afghanistan was one of the world's poorest countries even before a U.S.-led bombing campaign, launched in retaliation for the September 11 attacks on New York and the Pentagon.

Kabul's interim leader, Hamid Karzai, promised to create a credible government to undertake the rebuilding but said the money was needed quickly to shore up his administration.

"I stand before you today as the citizen of a country that has had nothing but disaster, war, brutality and deprivation against its people for so many years," the soft-spoken tribal chief said, clad in his trademark purple and green Uzbek robe.

Donors agree that rebuilding Afghanistan is vital, but want to be sure the money is not wasted or funnelled into the hands of rival warlords in a country still rent by internal strife.

Karzai sought assurances the world would not again turn its back on his country and that aid would flow fast enough to keep his fragile government from losing credibility with the people.

"While we understand the procedural requirements for the delivery of international aid, unfortunately, we have seen little sign from the international community in response to our urgent needs," Karzai said.

Life expectancy in Afghanistan is 44 years, one in four children dies before age five and only three in 100 girls are enrolled in primary school. Clean water is a luxury.

"We have one fear: that without the full partnership of the international community, Afghanistan may falter again," Karzai added.

U.S. Secretary of State Colin Powell, who told the conference the United States would provide $296 million in aid this fiscal year and more later, vowed Washington would not walk away.

"President Bush has made it clear that the United States will not abandon Afghanistan," Powell said.

Donors, however, want to make sure the assistance is well accounted for and that corruption does not lead the funds astray.

"The fact that Afghanistan is starting from scratch doesn't mean we ought to look the other way," U.S. Treasury Secretary Paul O'Neill told reporters accompanying him on his trip.

Asked about fears the aid would find its way into warlord's coffers, O'Neill said: "People do desperate things if they're desperate. It's not something we have six months to think about.

"We need to support them and we need to get money flows, but the money flows need to get goods and services, not just buy people off."

Donor countries also want proof that Karzai has a plan for creating a viable economy and a democratic society, concerns that Karzai sought to address.

"Although the interim administration has been in place for only one month, we have already agreed on a vision for the road ahead. Our vision is of a prosperous and secure Afghanistan," he said.

Pledging to create a free market economy and crack down on corruption, Karzai said the government would hire a reputable international firm to audit its expenditures regularly.

He also confronted two other concerns expressed by donors, saying his administration was fully committed to the education of girls, who were banned from going to school under the former Taliban rulers, and to making sure Afghan farmers did not slip back into the production of poppies for the world drug trade.

The World Bank and the United Nations have estimated that Afghanistan needs $1.7 million in the first year, $4.9 in the first 30 months and $10.2 billion in the first five years.

Kabul's government said it was "thrilled" by the first day's pledges and urged that the money be disbursed soon.

"The administration will make certain it will act responsibly with all pledges and hopes that the money will reach Afghanistan as soon as possible to initiate real work," spokesman Omar Samad said in a statement obtained by Reuters.

Some donors and aid agency officials, however, fear that Afghanistan cannot absorb such a deluge of cash.

"We've seen this in crisis after crisis. Countries need everything but they have no systems," said Clare Short, Britain's international development secretary.

The European Union pledged 550 million euros ($487 million) for 2002. Of that total, 200 million will come from the European Commission and the rest from member states.

The European Commission, the EU's executive branch, said it aimed to provide a total of one billion euros over five years.

Saudi Arabia, a former ally of the Taliban, promised $220 million over three years.

India pledged $100 million for long-term reconstruction and offered one million tonnes of wheat, as promises from a slew of other countries rolled in.

World Bank President James Wolfensohn said that he would propose to the Bank's shareholders $500 million in concessional aid over the next 30 months, and the Asian Development Bank said it planned to provide an equal amount over the same period. (Additional reporting by Stuart Grudgings, Alan Wheatley, Timothy Large, Jason Szep and Masayuki Kitano) Nampa-Reuters