Homeland Security Secretary Kristi Noem announced on Tuesday that the full stretch of the wall on the southern border with Mexico will be painted black. This decision, attributed to President Trump, aims to make the wall hotter under the sun to discourage illegal immigration.

Noem spoke during a visit to a portion of the wall in New Mexico, where she also picked up a roller brush to help out with the painting.

Noem highlighted the wall’s significant height and depth as measures to prevent crossings over and under it. Additionally, she mentioned the strategy of using black paint to heat the metal surfaces as a deterrent.

“This initiative comes at the president’s request, who believes that painting the wall black will increase its temperature during hot weather, making it more challenging to climb. We plan to paint the entire southern border wall black to discourage illegal entry into our country,” Noem explained.

U.S. Border Patrol Chief Mike Banks, who attended the event with Noem, said the paint would also help deter rust.

During Trump’s initial term, constructing the border wall was a pivotal component of his strict immigration agenda. Now, in his second term, the focus has shifted to mass deportations and increased arrests within the U.S. However, with new funding from Congress allocated earlier this summer, about $46 billion will be used to finalize the wall.

Noem said they have been building about a half mile of barrier every day.

“The border wall will look very different based on the topography and the geography of where it is built,” she said.

Aside from reinforcing physical barriers like the one she assessed on Tuesday, Noem mentioned the department’s efforts in developing “water-borne infrastructure,” as extensive parts of the 2,000-mile boundary with Mexico run along Texas’s Rio Grande River.

Even as the Trump administration advances its plans to complete the wall, there has been a significant drop in the number of individuals attempting to cross the border unlawfully.