The Trump administration is sending more than 2,100 additional troops to the southern border, the Pentagon said in a statement Wednesday.

The big picture: 1,000 Texas National Guard and 1,100 active duty troops will be sent to the border, as President Trump's rule requiring immigrants to seek refuge in a 3rd country before applying for asylum in the U.S. comes into effect. The troops will join about 4,500 active duty and National Guard troops already at the border, per Reuters.

Go deeper: It's taking longer and longer to become a legal immigrant