TUCSON — As President Donald Trump pushes Congress to set aside more money to build additional barriers along the U.S.-Mexico border, he frequently, and falsely, claims that his promised wall would help stem the flow of illegal narcotics into the country.

But data from his own administration repeatedly show that a rising number of smuggled drugs, especially more potent ones like heroin and cocaine, are increasingly seized at legal ports of entry, which are not impacted by a wall.

During a press conference Friday in the White House Rose Garden, Trump went so far as to claim that "drugs are pouring into this country," but that "they don’t go through the ports of entry."

"When they do, they sometimes get caught.”

Trump's comment conflicts with the numbers compiled by U.S. Customs and Border Protection, the agency responsible for enforcing the nation's laws along the U.S.-Mexico border.

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The agency posted on its website the amounts of drugs seized in fiscal year 2018, but is missing data from September. The agency has not updated the totals because of the partial government shutdown, which has put restrictions on its communications offices.

Hard drugs seized at ports of entry

According to the latest data available, while the largest amounts of drugs overall were seized in between the ports of entry, the overwhelming majority of those seizures by Border Patrol agents is for marijuana, which is cheaper and less strong than other narcotics.

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However, customs officers staffing the ports seized far greater quantities of hard drugs, such as methamphetamine, cocaine, heroin and fentanyl, which are not only more potent and deadly, but are also smuggled in smaller quantities.

As an example, agents seized more than 439,000 pounds of marijuana in the areas they patrol in between the ports last year. By contrast, customs officers seized more than 283,000 pounds at the legal border crossings during that same time.

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"When there's places here in the U.S. that you can get it (marijuana), I think it sends the message to the organizations that are smuggling marijuana that there is just not a need for that commodity any more," Rodolfo Karisch, the chief agent for Border Patrol's Tucson Sector, told The Arizona Republic last year.

However, customs agents also seized more than 67,000 pounds of methamphetamine smuggled through the ports of entry. Meanwhile, border agents seized nearly 10,300 pounds of meth last year.

Where wall would make a difference, drug smuggling has been decreasing

Customs officers at the ports also seized far greater numbers of cocaine, heroin and fentanyl, which is 50 times more potent than heroin, according to the Centers for Disease Control and Prevention.

While border agents seized 332 pounds of the deadly opioid, customs officers at the ports seized 1,357 pounds during that same time.

THE WALL: Drug smuggling, and the endless battle to stop it

Historical data also shows that the amounts of drugs smuggled in between the ports of entry, where a wall might make a difference, is on the decrease. The total number of marijuana seized in 2017, the last full year of data available, is almost a third of what it was in in 2012.

On the other hand, the smuggling of hard drugs is on the rise at ports of entry, with notable increases in the past five years, according to Customs and Border Protection.