A new report is urging governments and international organizations to do more to help rebuild Afghanistan. The report, which comes just days before a donor conference is held Berlin, highlights the cost of failing to adequately reconstruct the war-torn country.

The international community faces a stark choice, either increase aid to rebuild Afghanistan or watch it fall prey to extremists and criminals, according to the report. Issued by New York University's Center on International Cooperation, or CIC, the report says donor countries must devote more time and money to help Afghanistan.

Barnett Rubin, director of studies at the center, said the current level of assistance is not enough. "If the international community maintains more or less the level of assistance thus far, they will never be able to leave Afghanistan because it simply is not sufficient to enable the economy to take off and provide a basis for building sustainable governance there," he said.

Mr. Rubin estimates that Afghanistan will need almost $28 billion in aid over the next seven years to successfully rebuild itself. He says failing to provide the necessary funding will send Afghanistan into a downward spiral.

The CIC report says one of the biggest roadblocks to putting Afghanistan on a path toward self-reliance is the large criminal element in its economy. Opium production and drug trafficking now account for 33 percent of Afghanistan's economy, according to the report, and the percentage is expected to go higher.

In addition, attacks on aid workers are increasing, and in many parts of the country local warlords, not the central government, are in control of security.

Mr. Rubin warns this combination of poor security and a criminalized economy is fertile ground for the Taleban to come back to power or even for terrorists to return to Afghanistan. "If the country is insecure, and there's no effective administration, people are subjected to abuse of various types by armed groups that are funded by drug trafficking. Then that means there's no effective security institutions to prevent the re-establishment of terrorist bases and it also means that the Taleban will have an open field politically because they based their support previously on eliminating the warlords and commanders who were abusing people," he said.

At the Berlin donor meeting, which takes place later this week (March 31 to April 1), Afghanistan's interim government will present its plan on Afghanistan's reconstruction. This includes asking for $4.5 billion in aid this year. Because budgeting constraints do not allow many countries to pledge funding for more than one year at a time, the Afghan government is expected to ask donor countries to publicly acknowledge that it will cost nearly $28 billion to rebuild Afghanistan. A statement like that, Mr. Rubin says, would show the Afghans that they have the support of the international community.