The US is to spend $1m (£490,000) to help governments in Central America and Mexico combat violent criminal gangs.
Violent Central American street gangs are known as maras
State department official Thomas Shannon made the pledge while in Guatemala to sign a regional security-sharing agreement.
The money will be spent on improving intelligence sharing and co-operation, and police training.
Gangs are considered responsible for raising crime and murder rates in Guatemala, Honduras and El Salvador.
Mr Shannon said the violent criminal groups, know as maras, were also involved in drug trafficking.
The US Drug Enforcement Agency says about much as 75% of Colombian cocaine passes through Central America on its way to the US.
However, the aid package is minor when compared with the investment Washington makes in Colombian security, which stands at more than $500m a year, correspondents say.
Mr Shannon said once security co-operation was improved, it would be easier to convince the US Congress to increase aid.