In this April 29, 2018 file photo, a member of the Central American migrant caravan, holding a child, looks through the border wall toward a group of people gathered on the U.S. side, as he stands on the beach where the border wall ends in the ocean, in Tijuana, Mexico, Sunday, April 29, 2018. Associated Press/Hans-Maximo Musielik

The amount of arrests for illegal border crossings is expected to remain high for the month of May, Trump administration officials and Border Patrol agents told The Washington Post.

The development shows that the Trump administration's recent efforts to crack down on the border have not immediately produced the deterrent the White House had hoped for.

Officials are reportedly bracing themselves for an outburst from President Donald Trump.

He has grown enraged over the rising arrest numbers and berated Homeland Security Secretary Kirstjen Nielsen.

The Trump administration's recent efforts to crack down on the US-Mexico border by deploying National Guard troops and separating migrant parents from their children has reportedly failed so far to deter illegal border crossings.

The Department of Homeland Security is preparing to publish its monthly report on the amount of border-crossing arrests made in May. The Washington Post reported that the arrest totals are expected to be at least as high as they were in March and April, during which Border Patrol made more than 50,000 arrests each month.

The number of illegal crossings "is going to go higher and higher yet," one Trump adviser told The Post. "You're going to see a line that goes up all summer long."

Though the monthly arrest totals still hover near the bottom of a 40-year low, the recent numbers are significantly higher than what they were at the same time last year, when Border Patrol made roughly 16,000 arrests per month in March and April.

President Donald Trump has reportedly been enraged by the uptick, and has taken his frustrations out on his Homeland Security Secretary Kirstjen Nielsen.

Multiple reports have surfaced in recent weeks saying Trump has berated Nielsen in front of colleagues and fellow cabinet members over the monthly arrest reports, even at one point prompting her to draft a resignation letter.

Trump administration officials told The Post they were bracing for an "eruption" from the president when May's numbers are published.

To curtail the rising numbers, the government in April began deploying thousands of National Guard troops to help secure the border, though it's still unclear how effective their work has been.

The troops are barred from arresting or detaining migrants, and multiple Border Patrol union leaders recently complained to the Los Angeles Times that the deployment has been a "colossal waste of resources" that has yielded "no benefit."

In another highly controversial move, the Trump administration also imposed a "zero tolerance" policy, mandating that all migrants caught crossing the border illegally be criminally prosecuted - a process that separates migrants from any children they brought with them.

"If you cross the southwest border unlawfully, then we will prosecute you ... If you are smuggling a child, then we will prosecute you and that child will be separated from you as required by law," Attorney General Jeff Sessions said in early May. "If you don't like that, then don't smuggle children over our border."

The Trump administration has faced significant backlash from the public over the policy, which has been criticized as cruel and inhumane, but the White House has insisted that it will serve as a deterrent.

"The bottom line is Congress needs to act and close loopholes that serve as a tremendous pull factor for illegal immigration," DHS spokesman Tyler Houlton told The Post. "The Trump administration is restoring the rule of law by increasing prosecutions of illegal border crossers."

NOW WATCH: Popular Videos from Insider Inc.