Obama administration and Mexican government officials recently discussed creating a three-tier security system designed to protect Mexico’s southern border from drug and human traffickers, according to U.S. officials.

The border control plan calls for U.S. funding and technical support of three security lines extending more than 100 miles north of Mexico’s border with Guatemala and Belize. The border security system would use sensors and intelligence-gathering to counter human trafficking and drug running from the region, a major source of illegal immigration into the United States.

According to the officials who discussed the U.S.-Mexican talks on condition of anonymity, the Mexican government proposed setting up three security cordons using electronic sensors and other security measures along the southern Mexican border, along a line some 20 miles from the southern border, and along a third security line about 140 miles from the southern Mexican territorial line.

The plan would be funded in part through the Merida Initiative, a U.S.-led anti-drug trafficking program that has involved nearly $2 billion in U.S. funds.