The top U.S. Defense Department official for Latin America expressed concern Thursday that a crackdown on the drug trade in Colombia, Mexico and the Caribbean is leading traffickers to seek refuge in Central America, posing a potentially destabilizing threat to the region.

“They’re being squeezed in some of these other areas, they’re gravitating towards Central America,” Deputy Assistant Secretary of Defense for Western Hemisphere Affairs Frank Mora said at an event on hemispheric security at the Brookings Institution in Washington. “We within the United States—and not just the United States, the hemisphere, in fact the international community—should be able to think about what the challenge represents, not just to us, but to the stability of Central American countries,” he added.

Under the Mérida Initiative and other anti-narcotics cooperation programs, the U.S. Congress has appropriated some $1.3 billion to Mexico through January of this year, while Central American countries received just $248 million.

Mora said the United States needs to be more “aggressive in cooperating with our Central American friends,” citing as progress next week’s scheduled visit by Secretary of State Hillary Clinton to the region and an upcoming trip by a Pentagon delegation.

In response to Mora’s comments, Guatemalan Ambassador Francisco Villagrán de León said his country’s president, Álvaro Colóm, told Clinton in a meeting last week that Guatemala’s security forces are “overwhelmed” by the challenges posed by drug cartels. “[Colóm] sees a strong need to widen the role of the Guatemalan military, particularly in ensuring that the border with Mexico, the border with Belize can be secured,” Villagrán de León said.

With budgetary constraints and the U.S. fighting wars in Iraq and Afghanistan, Mora said the Defense Department lacks the resources to invest heavily in new Central American programs. However, he added a lack of resources shouldn’t be interpreted as a lack of commitment. “We tend to measure engagement by how many dollars the United States spends, and I think that’s the wrong criteria to use.”