U.S. leaders believe the attacks were masterminded by Osama bin Laden, a Saudi-born dissident who is sheltered by the Taliban regime.
"It would be a humanitarian catastrophe for millions of Afghans, reduced to misery by decades of war and, more recently, by the Taliban fundamentalist regime," said a spokesman for the U.N. humanitarian office for Afghanistan in Geneva.
In fact, the tragedy has already begun. Hundreds of co-workers have left the country, following the terrorist attacks in the United States. As a result, many aid programs have been interrupted.
To date, some 3 million Afghans have survived thanks to the assistance of the U.N. World Food Program, which in recent months has had problems with the Taliban regime.
According to data of the U.N. humanitarian office for Afghanistan, close to 6 million of the country´s 20 million inhabitants are in a "vulnerable" situation.
Eighty-five percent of Afghanistan´s inhabitants live in rural areas. Many have experienced war for 22 years. Most Afghans struggle daily to find food for their families.
Lacking transport, the majority of the people are unable to leave the country. Today, Pakistan virtually closed its borders to Afghan refugees. Earlier, Iran did the same.
There is growing fear in Islamabad that Afghans, who are loyal to the Taliban, will organize attacks in the country, if the United States or the West launches retaliatory strikes.
In recent months, 170,000 Afghan refugees, fleeing from war and drought, have crossed the border into Pakistan. Last year Pakistan was already implementing a policy for their expulsion.
Over 20 years, Pakistan has received a total of 1.2 million refugees. About 1.3 million Afghans live in Iran.
The Taliban leaders, meanwhile, are preparing for war. On Sunday, in a 17-minute radio speech, Mullah Mohammed Omar, spiritual leader of the Taliban, recalled the many invasions suffered by the country, particularly the Soviet invasion of the 1980s, and urged the people to give their life for Islam.
The Taliban regime, which has been in power for four years and controls 95% of the territory, has been recognized only by Saudi Arabia, Pakistan and the United Arab Emirates.
U.N. sources in Geneva said that the United States faces the challenge of bringing to justice those responsible for the attacks on New York and Washington, without killing thousands of innocent Afghan civilians.