Pentagon awaiting new request from DHS that could send more troops to border

After President Donald Trump told White House reporters on Friday that "we're gonna put more troops on the border," the Pentagon was awaiting a new request over the weekend from the Department of Homeland Security for more support along the Southwest border said the Pentagon's top official.

Previous discussions about what further role the U.S. military may play along the border with Mexico, according to one U.S. official who spoke to ABC News, included the prospect that the military could be used to build and manage tent cities to house migrants at two locations along the southwest border.

There are currently 3,900 active duty forces and 2,100 National Guardsmen serving on the southern border in separate missions supporting Customs and Border Protection.

Acting Defense Secretary Patrick Shanahan had earlier told reporters at the Pentagon that he expected an increase in U.S. military support to the Pentagon.

"It shouldn't come as a surprise that we would provide more support to the border," Shanahan told reporters.

"Our support is very elastic and given the deterioration there at the border you would expect that we would provide more support," he said.

However, Shanahan also said that the Pentagon had not received a formal Request for Assistance" (RFA) from the Department of Homeland Security.

" But we've been having a number of conversations with DHS," said Shanahan who added that this weekend a Pentagon planning team will follow up on what more support the Pentagon can provide along the border.

"Where are we on barrier construction? Where do we stand on the current support? and then on the areas we anticipate, What type of preliminary planning should we be doing prior to receiving that request for assistance," said Shanahan.

Like the previous RFA’s from DHS, the new one will list the additional capabilities that the agency needs along the border. Those capabilities will likely require more troops, but the exact number of troops will depend on how the Pentagon matches up what it can provide to meet the request from DHS.

A U.S. official said the Pentagon's discussions with DHS have included discussion of whether the U.S. military could be used to build and manage tent cities for migrants at two locations along the southern border

Another official said once the Pentagon receives the request from DHS, it will have to be reviewed to ensure that the requested capabilities fall under the legal restrictions for U.S. military troops operating domestically under the Posse Comitatus Act.

That would include whether the U.S. troops could interact with migrants should there be a request for a tent city to house detained migrants.

A Pentagon spokesman acknowledged that in the past the U.S. military has provided facilities to house migrants, but has not been involved in detention operations.."We’ve never engaged in that and I don’t know if we have any plans to do anything like that,” said Pentagon spokesman Charlie Summers.