The sun sets behind a C-17 Globemaster as soldiers wait in line to board the aircraft.

WASHINGTON — President Donald Trump said Wednesday he may deploy as many as 15,000 troops to the southwest border ahead of a caravan of Central American migrants.

"As far as the caravan is concerned, our military is out... we'll go up to anywhere between 10 and 15,000 military personnel, on top of Border Patrol, ICE and everybody else at the border," Trump told reporters before traveling to Florida.

A day prior, the four-star general overseeing the deployment, said the Department of Homeland Security requested 5,239 troops and that the figure was poised to rise.

"We do know that the 5,239 is — going forward and I will — what I can confirm is that there will be additional force over and above the 5,239," U.S. Air Force Gen. Terrence O'Shaughnessy told reporters at the Pentagon on Tuesday.

O'Shaughnessy, however, noted that he had yet to hear of a figure as high as what the president described.

"The numbers, for example, I heard 14,000 [troops] out there. I honestly don't even know where that came from. That is not in line with what we've been planning," he said.

The Department of Defense estimates that more than 7,000 troops will be positioned in California, Arizona and Texas in support of the Department of Homeland Security and Customs and Border Protection. The border mission, dubbed Operation Faithful Patriot, will have a larger U.S. military footprint than the combined efforts in Iraq and Syria.

In mid-October, a caravan of at least 3,500 Central American migrants left Honduras for the United States border. The caravan is currently in southern Mexico.

Meanwhile, Defense Secretary James Mattis downplayed criticisms Wednesday that the active-duty troop deployment to the border was a political stunt motivated by the midterm elections.

"The support that we provide to the secretary for homeland security is practical support based on the request from the commissioner of customs and border police. We don't do stunts in this department," Mattis said.

Earlier in the week, Trump told Axios that he would terminate birthright citizenship for non citizens and undocumented immigrants.

"We're the only country in the world where a person comes in and has a baby, and the baby is essentially a citizen of the United States ... with all of those benefits," Trump said Monday. "It's ridiculous. It's ridiculous. And it has to end."

"It's in the process. It'll happen ... with an executive order," Trump added.

Despite Trump's claim, Canada and many other countries grant birthright citizenship.

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