The United States expects to complete PresidentDonald Trump's long-promised southern border wall by late 2027, Customs and Border Protection (CBP) Commissioner Rodney Scott said Tuesday.

The barrier along the US-Mexico border is made of reinforced metal beams and is intended to run from San Diego to the Gulf ofMexico, except in selected areas "where we've made a conscious decision that we don't need it," Scott said at the Center for Immigration Studies event in Washington.

"The primary border wall will be done by the end of 2027," he said.

"There's a couple of gaps," Scott said. "The only places we're not building a border wall is places where we've made a conscious decision that we don't need it. Big Bend National Park, for example -- super remote area, some very, very high cliffs."

The wall will be supplemented by electronic surveillance and other devices, which would be installed by "about July, maybe at the latest August 2028," Scott said.

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The long stretch of the Rio Grande along the border ofTexas, which runs more than 1,200 miles (1,900 km) between the two countries, will have its own physical barriers.

"We'll have the entire system to include a secondary barrier in places we need it -- thewaterbarrier and the Rio Grande River -- and the technology," Scott said.

The wall is intended to curb illegalimmigrationand narcotics trafficking from Mexico, which have declined, according to official indicators.

But the physical barrier won't be enough to curb clandestine activities, Scott said. Tunnels,dronesand other workarounds are already being used to spot patrols and movedrugs.

"We'd see the drones flying along the Rio Grande River watching and videotaping where all our guys are. That is theirbusinessmodel, and drones definitely make it easier," Scott said. "They're also smuggling narcotics across with drones."

(FRANCE 24 with AFP)

Originally published on France24