Faced with an increasing flow of Central American migrants north, Mexico plans to set up a "containment" belt of federal forces across the Isthmus of Tehuantepec, which is the narrowest part of the country's south and the easiest to control, a senior government official said Wednesday.

Interior Secretary Olga Sanchez Cordero said the situation is complicated by a caravan of roughly 2,500 migrants heading north and fears of a much larger "mother caravan" possibly forming in Honduras.

"We are going to locate our migration installations, of Federal Police and civil protection, harmoniously and with collaboration among all the federal government agencies in such a way that we have containment in the Isthmus of Tehuantepec," she said in comments a day after meeting with U.S. Secretary of Homeland Security Kirstjen Nielsen. "It's going to be a big change."

Sanchez Cordero did not provide more details about how the federal forces would be deployed, but she stressed it would not mean the militarization of Mexico's border with Guatemala.

Nielsen was in Honduras on Wednesday for a meeting with Central American officials.

A new migrant caravan of about 2,500 people, mainly from Nicaragua, Cuba, El Salvador, Honduras and Guatemala, was making its way through southern Mexico this week, headed for the U.S. border. But the migrants were not receiving the same warm welcome as previous caravans. Activists said the Mexican government was trying to wear the caravans out, or stop them from trying to reach the United States.