Perry, who is mulling a second presidential run after his 2012 bid flamed out in a series of public gaffes, spent part of the weekend in Iowa, where he questioned President Barack Obama's commitment to securing the border and said Texas would do so if the federal government did not.

State Rep. Terry Canales said he was briefed by his staff Sunday following a conference call with the governor's office, the Texas National Guard and the state Department of Public Safety. Perry's office hasn't commented, but he is scheduled to make the announcement Monday afternoon at the state Capitol in Austin.

More than 3,000 Border Patrol agents currently work in the region, and Perry has repeatedly asked Obama to send the National Guard to the border. Much of the area has been overwhelmed in recent months by tens of thousands of unaccompanied children illegally entering the U.S.

U.S. Customs and Border Protection didn't immediately respond to a request for comment Monday. The governor's plans were first reported by The Monitor newspaper in McAllen, Texas.

As governor, Perry is commander in chief of Texas military forces unless those forces have already been mobilized by the White House. President George W. Bush sent 6,000 National Guard troops to the border in 2006, and Obama eventually extended that deployment while ordering a second wave of National Guard forces to Texas, California, Arizona and New Mexico in 2010. But the second round saw reduced numbers of troops, and most of their work was limited to air patrols in counterdrug operations.

Perry announced last month that Texas would steer another $1.3 million each week to the Department of Public Safety to assist in border security through at least the end of the year. In a letter to Obama on June 20, Perry made several requests for help along the border, including 1,000 National Guard troops, additional helicopters and giving troops "arrest powers to support Border Patrol operations until sufficient Border Patrol resources can be hired, trained and deployed to the border."

It's not clear why Perry would need the Obama administration to authorize arrest powers and the governor's office has not offered details ahead of the announcement. Texas law simply states that the governor can "adopt rules and regulations governing enlistment, organization, administration" of the Texas State Guard.

In a White House letter to Perry on July 7, Obama adviser Valerie Jarrett laid out steps the administration was taking to deal with what the president had called an "urgent humanitarian situation," but did not mention the National Guard. Obama met with Perry two days later in Dallas, and the administration has worked with Mexico and other countries the immigrants are leaving to make it clear they will not be allowed to stay in the U.S.

On previous border deployments, National Guard soldiers have served in support roles — administrative, intelligence gathering — while the Border Patrol expanded its ranks. Some National Guard troops already participate in counter-drug operations on the border, though they don't have arrest powers.

Since October, more than 57,000 unaccompanied children and teenagers have entered the U.S. illegally — more than double compared to the same period a year earlier. Most have been from Honduras, Guatemala and El Salvador, where rampant gang violence and intense poverty have driven tens of thousands of people outside their borders.

Their numbers overwhelmed Border Patrol facilities in the Rio Grande Valley, leading Perry and the Texas Department of Public Safety to argue that Border Patrol agents distracted by groups of children and families were leaving gaps.

Most of those children have been turning themselves in to the first person in a uniform they see.

On Monday, Canales questioned Perry's plan of sending National Guard troops to the border.

"I don't understand what their tactic is, and I don't think it's going to work," the Democrat said.

He said the state may see a dip in the short term, but that such a surge by the state is unsustainable and the drug cartels would simply wait the troops out.

"They might get the desired effect, but it won't last long," he said.