"If the international community does not take immediate action, countless deaths and terrible tragedy are certain to follow," he told reporters, appealing for other countries to boost their assistance to Afghanistan.
The new US assistance, which includes 65,000 tonnes of wheat, five million dollars in other foodstuffs such as vegetable oil and 10 million dollars for refugees and internally displaced persons, brings to 124 million dollars the amount of aid Washington is providing this year to Afghans.
The United States is the largest single donor of humanitarian aid to Afghanistan despite not recognizing the legitimacy of the country's ruling Taliban militia and Powell reasserted US concerns about the fundamentalist Muslim group.
"Our aid bypasses the Taliban who have done little to alleviate the suffering of the Afghan people, and indeed, have done much to exacerbate it," he said.