The project aims curtail the flow of terrorists between the two countries. It follows a years-long Pakistani military push aimed at dismantling militant networks in its restive tribal North and South Waziristan regions.

"For the better security of our country and nation, we had to do this work," Pakistani army official Brig. Nisar, who only uses one name, told journalists during a government-organized visit to the border earlier this month.

The barrier has angered the Afghan government, which disputes the location of the boundary and says the fence will tear communities apart.