Walls won't stop migration," the Mexican government said Tuesday with reference to a Republican amendment to comprehensive immigration reform that calls for stronger border security.

"We're convinced that walls do not unite, they won't stop migration, and they're not consistent with a modern, secure border," Mexican Foreign Secretary Jose Antonio Meade told reporters.

The U.S. Senate passed on Tuesday "a plan to strengthen" security on the border with Mexico proposed by Republicans John Hoeven and Bob Corker.

The plan contemplates doubling to 40,000 the number of border agents, building walls and barriers along 1,126 kilometers (700 miles) of border, and surveillance by drones and other high-tech tools.

At the height of the immigration reform debate by U.S. senators, Meade recalled that the priority for Mexico is "to achieve a more modern, stable and humane migration system" that would benefit the millions of Mexicans living north of the border, many of whom are undocumented.

He said it is "indispensable to promote the modernization of border crossing points" and at the same time "improve their infrastructure and administration" in an area of voluminous bilateral trade and where "more than a million people cross every day."

He also recalled that during U.S. President Barack Obama's visit in early May, both governments agreed to work to make their shared border "a prosperous, secure, sustainable region and a promoter of development." EFE