ASUNCION (Reuters) – Paraguay has issued an open-ended suspension of arms and ammunition imports in a bid to fight illegal trafficking across the border into neighboring Brazil, the head of the National Directorate of War Material told Reuters on Tuesday.

During the suspension, the directorate will update computer programs it uses and improve coordination with Paraguayan and Brazilian law enforcement agencies, directorate chief Enrique Caballero said.

“We want to provide traceability,” he said. “The illicit market is our concern and we must increase efforts at stopping that.”

The move followed pressure from the United States, which imposed a three-month moratorium on arms sales to Paraguay as part of a concerted effort with the Brazilian government to clamp down on arms smuggling, according to a person familiar with the matter.

Studies by police in Brazil suggest many of the heavy rifles used by criminal gangs there were made in the United States and smuggled into the country via Paraguay.

Asked about efforts to crack down on arms smuggling in Paraguay, a U.S. Department of State official said: “We share the government of Paraguay’s concerns and are currently working together to assess the situation.”

Caballero did not provide data on the volume of Paraguay’s legal weapons imports and declined to comment on reports of the U.S. arms sale suspension.