WASHINGTON (Reuters) - The Pentagon said on Friday that it expected to send about 300 additional troops to the border with Mexico including roughly 100 cooks who would hand out meals, breaking with past policy to avoid troops coming in contact with migrants.

It is the latest sign of a growing U.S. military support role for President Donald Trump’s politically charged immigration policies.

Earlier this month, Trump said he would have to mobilize more of the military at the border with Mexico after listening to stories about migrants crossing the border from people attending a Republican fundraiser.

The Pentagon previously said there were no plans for U.S. forces to interact with migrants as they support border agents dealing with illegal immigration.

In addition to the cooks, the Pentagon is expected to send 160 drivers and 20 lawyers, Pentagon spokesman Charlie Summers said.

“We will have some of our troops handing out meals, therefore (they) would come in contact with migrants,” Summers said. He said it was an “amendment to the current policy.”

U.S. troops are assisting Border Patrol agents who have been overwhelmed trying to cope with a surge in migrants seeking asylum. The Department of Homeland Security a few weeks ago redeployed about 750 officers to the border to deal with the surge, resulting in a slowing of legal crossings and commerce at ports of entry.

Summers said acting Defense Secretary Patrick Shanahan had not yet signed the request for assistance from the Department of Homeland Security, but he was expected to do so.

There are currently about 5,000 active-duty and National Guard troops near the border, though that number fluctuates.

There has been increasing concern about the military playing a growing role on the border with Mexico.

The Posse Comitatus Act, a federal law on the books since the 1870s, restricts using the U.S. Army and other main branches of the military for civilian law enforcement on U.S. soil, unless specifically authorized by Congress. But the military can provide support services to law enforcement and has done so on occasion since the 1980s.

Earlier this month six Mexican military personnel questioned two U.S. Army soldiers near Clint, Texas. A U.S. military investigation found the American soldiers were in U.S. territory during the incident, while the Mexican personnel believed they were south of the border.

Trump has made immigration a signature issue of his presidency and of his re-election campaign. He declared a national emergency over the issue earlier this year in an effort to redirect funding from Congress to build a wall along the U.S. southern border.