UPDATE | Trump signs order to send troops to US border

WASHINGTON (AP) — President Donald Trump signed a proclamation tonight directing the National Guard to be deployed to the U.S.-Mexico border.

Trump says in a memorandum to his secretaries of defense and homeland security and to his attorney general the "situation at the border has now reached a point of crisis."

The document orders the Secretary of Defense to support the Department of Homeland Security in securing the southern border to stop the flow of drugs and people.

And it orders the agency heads to submit a report within 30 days outlining what other steps can be taken.

Trump says "lawlessness" at the southern border is "fundamentally incompatible with the safety, security, and sovereignty of the American people." And he says his administration "has no choice but to act."

8 p.m.

WASHINGTON (AP) — President Donald Trump and border-state governors are working to "immediately" deploy the National Guard to the U.S.-Mexico border to fight illegal immigration, Homeland Security Secretary Kirstjen Nielsen said today.

"The threat is real," Nielsen said, adding that Trump was signing a proclamation to put the deployment into effect. "It's time to act."

The announcement came hours after Trump pledged "strong action today" on immigration and a day after he said he wanted to use the military to secure the southern border until his long-promised border wall is erected.

Nielsen said she's been in touch with governors on the southwest border states and has been working with them to develop agreements that will oversee where and how many Guardsmen will be deployed.

She suggested some troops could begin arriving as soon as tonight, though other administration officials cautioned that details on troop levels, locations and timing were still being worked out.

"We do hope that the deployment begins immediately," she said.

Trump has been frustrated by slow action on building his "big, beautiful wall" along the Mexican border – the signature promise of his campaign – as well as a recent uptick in illegal border crossings that had plunged during the early months of his presidency. He has also bothered the spending bill he grudgingly signed last month includes far less money for the wall than he desired.

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.