BOGOTA, COLOMBIA -- Just as new President Alvaro Uribe begins his term determined to combat Colombia's leftist guerrillas, the Bush administration has delivered a powerful new tool: authorization to use nearly $1.7 billion in U.S. military aid directly against the rebels.

Under a provision in the anti-terrorism package President Bush signed last week, Uribe can now use dozens of U.S.-supplied helicopters, as well as Colombian soldiers who were trained by U.S. troops, in operations against the rebels and also right-wing paramilitaries. Previous guidelines limited the use of the helicopters and soldiers to anti-drug operations, restricting Colombia's armed forces from using some of its best equipment and troops to fight the rebels.

The policy shift, coming at a time of escalating guerrilla violence, represents a significant intensification of U.S. involvement in the long and intractable conflict in this country. This week the rebels launched a mortar attack in the capital during Uribe's inauguration.

The redirection of aid came after Colombian officials and their U.S. supporters in Congress and the Bush administration argued that the change came under the umbrella of the global campaign against terrorism.

U.S. troops will continue to be barred from participating in Colombia's 38- year-old conflict. But the package includes $6 million for an oil pipeline protection program that will involve the training of a new Colombian army unit by U.S. soldiers. The pipeline, crucial to Colombia's economy, is frequently bombed by rebels.

The legislation, part of a broad $28.9 billion supplemental package, says that military aid already provided to Colombia "shall be available" against "activities by organizations designated as terrorist organizations" by the State Department. Those organizations are identified as the Revolutionary Armed Forces of Colombia, or FARC, the country's largest guerrilla group; the National Liberation Army, a smaller left-wing insurgency; and the nemesis of both, the right-wing United Self-Defense Forces of Colombia, which is financed by landowners to battle the rebels.

All three groups have drawn much of their financing from protecting or participating in the drug trade.

A State Department official said the legislation "removes an ambiguity in the law." He explained that under previous guidelines, U.S.-trained troops using U.S. helicopters could not attack a guerrilla column or stop a rebel attack.

"That has all changed," he said. Now they can go after guerrillas, he said, although the equipment and troops will still be used against drugs. "The equipment is now available for both," he said.

U.S. congressional aides said the authorization goes into effect immediately. But there are requirements for Uribe. Under the terms, which the government has accepted, it must devote more money to the army while establishing comprehensive policies to combat drugs, bring government authority to rural areas and ensure respect for human rights.

Colombian officials say the change greatly enhances the army's combat capability. Most of the benefits come from 53 helicopters, 14 of them high- tech Blackhawks, that Colombia's army has received as part of the $1.1 billion Plan Colombia aid package Washington approved in 2000. Another 19 helicopters, all of them Huey IIs, will arrive by mid-fall.

The guidelines also mean that Colombia will be able to use a 3,000-man counterdrug brigade trained by U.S. Special Forces directly against the rebels.

The brigade has, until now, focused on securing dangerous, drug-controlled regions to allow crop dusters to fumigate without being attacked by rebel forces.

"It will give us more mobility, much more capacity, much more firepower," said Francisco Santos, Uribe's vice president.

Bush administration officials emphasize that the equipment and U.S.-trained troops will still primarily be used for counterdrug operations. Congress will decide if $500 million in military and police aid being proposed in 2003 can also be used directly against the rebels. Since 1999, the United States has provided Colombia with a total of $1.7 billion in military aid, making this nation the third-largest recipient of U.S. assistance.

The shift in policy has concerned human rights groups and some members of Congress, who say escalating violence may become a byproduct of the redirected aid.

Copyright 2002 The New York Times Company

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