President Donald Trump has a few ideas for the construction of the U.S.-Mexico border barrier that he's promised his supporters.

The president has suggested painting the steel bollards with "flat black" paint that would soak up a lot of heat in the scorching desert sun, according to a Washington Post report. The blistering heat would make it nearly impossible for illegal immigrants to climb the steel slats.

Summer temperatures easily reach into the 110s or higher in border towns including Yuma, Arizona, and McAllen, Texas, according to the Weather Channel.

Trump has reportedly insisted that the top of the 30-foot tall bollards be pointed as a secondary deterrent for climbers. He allegedly described how the sharp tips would cut the hands of illegal crossers who tried to climb over it.

The information reportedly came from unnamed Homeland Security officials, White House aides, and officials and military engineers.

During construction update meetings, Trump questions engineers and others about whether or not illegal immigrants would be able "cut a hole in it, dig under it, climb over it."

The current blueprints also include gates placed at various points along the border wall to allow vehicles to drive through, but Trump reportedly wants the passages to be smaller.

Where's the money for the wall?

The Pentagon announced on Wednesday that it awarded more than $787 million in combined contracts to start construction and replacement projects along the southwest U.S.-Mexico border in California and Arizona, according to a news release.

On May 10, the Pentagon approved the re-allocation of $1.5 billion to start construction on a portion of the border wall, acting Defense Secretary Patrick Shanahan said.

"Today, I authorized the transfer of $1.5 billion toward the construction of more than 80 miles of border barrier," Shanahan told Fox News. "The funds were drawn from a variety of sources, including cost savings, programmatic changes, and revised requirements, and therefore will have minimal impact on force readiness."

Officials approved another $1 billion toward the wall in March, UPI reported.

A month earlier, Democrats agreed to allocate $1.38 billion for the border barriers. Republicans had asked for $5.7 billion, but accepted the deal in order to avoid another partial government shutdown.

