KABUL, Afghanistan - To slow the flow of illicit drugs, terrorists and contraband into and out of Afghanistan, the United States is planning to finance the construction and maintenance of 177 checkpoints staffed by a 12,000-man border police unit, officials said yesterday.

The plan was revealed at an investment conference sponsored by the U.S. Embassy. Officials dangled hundreds of millions of dollars in prospective supply contracts and construction projects before a group of local and foreign business executives, hoping to spur interest in Afghanistan's reconstruction and to boost its economy.

Maj. Gen. Karl W. Eikenberry described the construction and supply of a border checkpoint chain as a "guaranteed market." The general, who is in charge of the U.S. training of a new Afghan army, did not say how the border police unit would be staffed.

Col. Jesse Munoz of the Army Corps of Engineers said the checkpoints would include offices, sleeping quarters and in some cases clinics, costing an average of $300,000. A contract to build the checkpoints could be awarded as early as April, and they could be in operation in two to three years, Munoz said.

In an interview yesterday, Arif Noorzai, Afghanistan's minister of frontiers and tribal affairs, said he had not been formally told of the U.S. plan. But he applauded a crossing network as vital to fighting terrorism and protecting the country's economy and environment.

The new checkpoints might also give President Hamid Karzai's government a way to collect more duties on imports and bolster its meager revenue base. Poor customs collections are one of many reasons the government has had to rely on international donors to finance four-fifths of its budget.

Smuggling is rife at crossings, especially along the heavily traveled frontier with Pakistan. So are exports of illegally cut Afghan timber, Noorzai said.

The United States has stressed that Afghanistan's recovery and pacification after decades of strife depend on the involvement of private investors, both domestic and foreign, in the reconstruction process. U.S.-funded public works projects represent prime investment opportunities.

"Security and reconstruction go hand in hand," U.S. Ambassador William B. Taylor, special emissary for donor assistance in Afghanistan, told those gathered at the embassy yesterday.

Chris Kraul is a reporter for the Los Angeles Times, a Tribune Publishing newspaper.