Washington - Deportations are being stepped up of illegal migrants along the US border, a top Obama adminstration official said on Sunday, defending the White House's handling of a flood of undocumented children.
Secretary of Homeland Security Jeh Johnson told NBC television's "Meet the Press" that officials have reduced the "turnaround times" for migrants illegally entering the country along the Mexican border.
"I believe we're going to stem this tide," said Johnson, who added that the administration also is intensifying efforts to discourage migrants, including thousands of unaccompanied children, from making the dangerous and difficult overland journey to the United States.
"There are no free passes once you get here" for those entering the US without authorisation, Johnson said.
"Our message to those who come here illegally: our border is not open to illegal migration. There is a deportation proceeding that has commenced against illegal migrants - including children," the domestic security chief said.
The immigration issue has gained new urgency in the United States after 52 000 unaccompanied minors crossed illegally into the US via America's southern border since October.
President Barack Obama is due to travel to Texas later this week, but Johnson would not say whether a visit to the state's border areas is on his agenda.
Democratic lawmaker Henry Cuellar said holes in US law were to blame for the massive immigrant influx into his state of Texas, especially from Central America.
"If you're a Mexican, you get sent back - mother, kids, adults, you're sent back," said Cuellar.
"But if you're a non-contiguous country like the Central American countries, then the law says that you are going to be held by [the federal Department of] Health and Human Services, and they're going to place you," Cuellar told CNN.
"That's the law that we need to change right now."
Cuellar accused the White House of being caught flat-footed by the crisis.
"It's not the first time we have seen a surge, and we should have been ready for this surge," Cuellar said. "The administration should have been ready."
Obama's Republican foes said the administration's policies encouraged the influx.
"What has to be addressed is the security of the border. You know that. I know that. The president of the United States knows that," said Texas Governor Rick Perry, speaking to ABC television.
"I don't believe he particularly cares whether or not the border of the United States is secure. And that's the reason there's been this lack of effort, this lack of focus, this lack of resources."
Senator Lindsey Graham said the administration was guilty of sending the wrong signals to migrants in Central America.
"This is a specific problem created by the impression that if you get to America, you can stay," said Graham.
"We've got to turn that impression around, send these children back home, and tell the countries in question if you don't keep them, we're going to cut all aid off."
Overwhelmed by the massive waves of mostly lone child migrants crossing from Mexico into Texas and Arizona, the US government has been forced to transfer some of them to detention centres elsewhere, including in California.
Last week, the tense debate took a contentious turn when residents of a California town refused to allow three busloads of undocumented migrants from Texas to relocate there.