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WASHINGTON - (AP) -- President Donald Trump said Tuesday he wants to use the military to secure the U.S.-Mexico border until his promised border wall is built.
Speaking during a visit with Baltic leaders, Trump said he's been discussing the idea with his Defense Secretary, Jim Mattis.
"We're going to be doing things militarily. Until we can have a wall and proper security, we're going to be guarding our border with the military," he said, calling the measure a "big step" that had rarely been done before.
Federal law prohibits the use of active duty service members for law enforcement inside the U.S., unless specifically authorized by Congress. But over the past 12 years, presidents have twice sent National Guard troops to the border to bolster security and assist with surveillance and other support.
The White House counsel's office has been working on the idea for several weeks.
Trump has been deeply frustrated about the lack of progress building what was the signature promise of his campaign: a "big, beautiful wall" along the Mexican border. He's previously suggested using the Pentagon's budget to pay for building the wall, arguing it is a national security priority, despite strict rules that prohibit spending that's not authorized by Congress.
The Department of Homeland Security and White House did not immediately respond to requests for comment. At the Pentagon, officials were struggling to answer questions about the plan, including rudimentary details on whether it would involve National Guard members, as similar programs in the past have done.
But officials appeared to be considering a model similar to a 2006 operation in which former President Bush deployed National Guard troops to the southern border in an effort to increase security and surveillance.
Under Operation Jump Start, 6,000 National Guard troops were sent to assist border patrol with non-law enforcement duties while additional border agents were hired and trained. Over the two years, about 29,000 National Guard forces participated in the missions, as forces rotated in and out.
Active duty U.S. troops weren't used for the operation because legal prohibitions.
In addition, President Barack Obama sent about 1,200 National Guard troops to the U.S.-Mexico border in 2010 to beef up efforts to battle drug smuggling and illegal immigration.
Texas has also deployed military forces to its 800-mile border with Mexico. Former Texas Gov. Rick Perry, now serving as Trump's energy secretary, ordered the deployment of 1,000 Texas National Guardsmen to the Rio Grande Valley in summer 2014 in response to a sharp rise in the numbers of Central American children crossing the border alone.
White House officials were scheduled to meet later Tuesday with DHS border security personnel and attorneys to discuss further details, according to a White House official speaking on condition of anonymity. The White House counsel's office has been working on the issue for some time, the person said..
The Posse Comitatus Act, passed after the Civil War, is the main federal law prohibiting the use of American service members in law enforcement, unless specifically authorized by Congress.
Trump's comments came a day after administration officials announced they were crafting a new legislative package aimed at closing immigration "loopholes" and Trump called on Republican lawmakers to immediately pass a border bill using the "Nuclear Option if necessary" to muscle it through, as part of a flurry of tweets on the subject over the last several days.
The president has also been declaring protections for so-called Dreamer immigrants "dead," accusing Democrats of allowing "open borders, drugs and crime" and warning Mexico to halt the passage of "caravans" of immigrants or risk U.S. abandonment of the North American Free Trade Agreement.
Trump has been seething since realizing the major spending bill he signed last month barely funds the wall he has promised supporters. The $1.3 trillion funding package included $1.6 billion in border wall spending — far less than the $25 billion Trump made a last-minute push to secure. And much of that money can be used only to repair existing segments, not to build new sections.
Among the new measures the administration is pursuing: ending special safeguards that prevent the immediate deportation of children arrested at the border and traveling alone. Under current law, unaccompanied children from countries that don't border the U.S. are turned over to the Department of Health and Human Services and undergo often lengthy deportation proceedings before an immigration judge instead of being immediately deported.
The administration is also pushing Congress to terminate a 1997 court settlement that requires the government to release children from custody to parents, adult relatives or other caretakers as their court cases proceed. Officials complain that many children never show up at their hearings.
Trump announced last year that he was ending DACA, the program that protects young "Dreamer" immigrants and allows them to work legally in the country, but the Department of Homeland Security is continuing to issue renewals because of a court order.
Trump also warned Mexico to halt the passage of about 1,100 migrants, many from Honduras, who had been marching in a caravan along roadsides and train tracks in the southern Mexican state of Oaxaca.
These "Stations of the Cross" migrant caravans have been held in southern Mexico for at least the last five years. After days of walking along roadsides and train tracks, the organizers now plan to try to get buses to take participants to the final event, an immigrants' rights conference in the central state of Puebla later this week.
"If it reaches our border, our laws are so weak and so pathetic," Trump claimed. "It's like we have no border."