Colombia's coca production climbs and efforts to cultivate substitute crops fail. New planes for drug spraying are not delivered. European contributions have been much less than expected. The South American country's commitment to human rights is in question.

Members of Congress are looking at what has been done with the $1.7 billion in aid they've given to Colombia over the last two years. They don't like what they see.

Colombian President Andres Pastrana will hear their complaints firsthand during his visit this week to Washington as he seeks broader U.S. support for his war against guerrillas.

``We're talking about a lot of money going to a very small area that is making zero progress,'' Rep. Sonny Callahan, R-Ala., said at a House Appropriations foreign operations subcommittee hearing last week. As the panel's chairman in 2000, Callahan was pivotal in getting the initial $1.3 billion aid package approved.

The criticism will make it difficult for Pastrana to win support for President Bush's proposal to expand U.S. aid beyond fighting drugs.

``You have to look at the past to make a decision for the future,'' said Rep. Ike Skelton of Missouri, the top Democrat on the House Armed Services Committee.

Administration officials acknowledge problems but say it's unfair to judge a six-year program after less than two years. They also claim some successes. Fumigation of coca has increased, drug laboratories have been dismantled and traffickers have been extradited to the United States. Alternative development programs have been changed to correct problems.

``To call things an abysmal failure, I think, is looking at the glass and saying it is half empty rather than looking at it and saying it's half full,'' said Mike Johnson, policy director at the Pentagon's counternarcotics office.

Administration officials say the United States needs to defend democracy in a pivotal part of South America. They warn that continued instability in Colombia may lead to more drug trafficking and terrorism. The United States considers Colombia's main guerrilla and paramilitary groups to be terrorist organizations.

Some of the biggest impediments to success in Colombia, aid supporters say, have been the very restrictions that Bush wants to eliminate. The president, who meets with Pastrana on Thursday, wants to end rules that limit Colombia's use of helicopters and other U.S.-provided equipment to drug-fighting operations. He also has proposed $35 million in anti-terrorism aid this year.

``I think it was not realistic to think that you could separate the drug problem from the national security problem,'' said Sen. Mike DeWine, R-Ohio.

The distinction between fighting drugs and fighting rebels is murky in Colombia. Guerrillas and paramilitaries partly finance their forces through the drug trade.

Lawmakers placed the restrictions hoping the United States could fight drugs in Colombia, the world's largest producer of cocaine, without getting bogged down in its civil war. They were also wary of the Colombian army's links to human rights abuses.

The $1.3 billion package was the U.S. contribution to Pastrana's $7.5 billion Plan Colombia, intended to fight drugs, bring peace and boost the economy. Major contributions were also expected from Europe.

Problems developed right away. The European support was much less than expected. New spray planes didn't arrive because the manufacturer went bankrupt.

Many Colombians opposed the spraying, saying it threatened their legal crops and health. The Bogota government suspended spraying operations several times. Colombians also made little progress in taking full control of the program, which depends heavily on State Department contractors to fly and maintain aircraft.

U.S. lawmakers have questioned Colombia's commitment not only to fighting drugs, but fighting guerrillas. They say the country doesn't spend enough on defense and shouldn't expect the United States to pick up the slack.

Reports emerged last month of problems in the crop-substitution program. A U.S.-funded study found that few farmers who had agreed to abandon coca, the raw material for cocaine, had done so.

The White House announced last month that coca production actually rose by about 25 percent last year. Colombia has denied this, saying its statistics show a 16 percent decrease.

``I don't think anybody is happy with where Plan Colombia is today,'' John Walters, the White House drug policy director, said. ``The question is where do we go from here?''

Administration officials have said the best way to fight drugs in Colombia is to help the country end the threat from guerrillas. Fighting has increased since peace talks with the main rebel group collapsed in February.

Walters acknowledged that diverting helicopters from anti-drug operations could weaken spraying programs, at least temporarily. That could prevent the United States from meeting its original goals of cutting Colombian drug production in half over six years.

But, Walters said, U.S. plans must be adapted to changing circumstances.

The rebels ``have dramatically increased their challenge to the government and that has to be met head on,'' he said.