SAN VICENTE DEL CAGUAN, Colombia -- President Clinton's proposed $1.3 billion anti-narcotics aid package for Colombia will only lead to more bloodshed, a leftist rebel spokesman warned Wednesday.

Interviewed in the rebel-held southern ranching town of San Vicente del Caguan, Commander Ivan Rios called the massive aid infusion announced Tuesday a "dangerous" step that will escalate fighting without reducing the flow of drugs to the United States.

"This is not the solution, but rather the worsening of the problem," said Rios, a midlevel commander of the country's largest guerrilla band, the Revolutionary Armed Forces of Colombia, or FARC.

In announcing the plan Tuesday to up U.S. aid to Colombia from $300 million last year, Clinton said it will "help Colombia promote peace and prosperity and deepen its democracy."

The money will go toward helping stem the production and export of illegal narcotics while supporting economic development and improving human rights, Clinton said.

The bulk of the aid will go toward special counternarcotics battalions in the Colombian military, whose principal activity is battling the rebels. The battalions will receive dozens of American-made helicopters for transporting troops and drug surveillance.

The ranking Democrat on the U.S. Senate appropriations subcommittee that oversees foreign spending said Wednesday that he wants the Clinton administration to better explain what it hopes to achieve with the plan and at what risk.

"We at least need to see a concerted effort by the Colombian Army to thwart the paramilitary groups, who are responsible for most of the atrocities against civilians, and a willingness by the Colombian Armed Forces to turn over to the civilian courts their own members who violate human rights," Sen. Patrick Leahy, D-Vt., said in a statement.

Trying to compel the Colombian rebels to negotiate by increasing counterinsurgency efforts is "a costly and dangerous policy," Leahy said.

While insisting that Washington is not getting involved in another counterinsurgency war in Latin America, U.S. officials concede that their anti-narcotics strategy now requires confronting the rebels.

Funds are also being provided to wean poor peasants away from planting coca and poppy, the illegal crops used to make cocaine and heroin. The rebels, who earn huge revenues by taxing the peasant growers, have pledged in peace talks to participate in crop-substitution programs.

Secretary of State Madeleine Albright is scheduled to visit Colombia this weekend to explain the aid package, which will be part of Clinton's fiscal 2001 budget.

Colombia's drug production has skyrocketed in the past few years despite increased law enforcement efforts here - primarily a U.S-backed program to help police raid jungle drug laboratories and to fumigate illegal crops from the air.

Those efforts are destined to fail, U.S. officials contend, as long as the 15,000-member FARC retains its grip on the southern regions where drug crops are growing the fastest. Police are outgunned by the rebels, who often fire on fumigation planes.

Fighting narcotics has long been the focus of U.S. policy in Colombia, the world's No. 1 source of cocaine and a growing heroin supplier.