Speaker of the House Nancy Pelosi and Senate Minority Leader Chuck Schumer said President Trump's national emergency declaration does "great violence" to the US Constitution.
In a joint statement, they said the so-called crisis at the border that Trump described "does not exist."
They urged their Republican colleagues to fight against the declaration.
"Just as both parties honored our oath to protect the American people by passing the conference committee bill, the Congress on a bipartisan basis must honor the Constitution by defending our system of checks and balances," they said. "The President is not above the law. The Congress cannot let the President shred the Constitution,"
Here's their full statement:
From CNN's Jeremy Diamond and Betsy Klein
Even as he prepares to sign a national emergency declaration, President Trump appeared to complain that the border security appropriations bill he will sign provides too much funding.
Still, he said, the one area where Democrats refused to give him sufficient funding is on the border wall -- hence requiring the national emergency.
Trump also lamented that he wasn't able to build the wall earlier in his presidency, blaming others who he said, "didn't step up."
"Would've been great to do it earlier, but I was a little new to the job," he said.
"People did not step up – would’ve been easy, not easy, but it would’ve been a lot easier, but some people didn’t step up," Trump said, apparently referring to the once-Republican controlled House.
"But we’re stepping up now."
Watch the moment:
As President Trump takes questions in the Rose Garden, press secretary Sarah Sanders tweeted a black-and-white photograph of the President signing the national emergency declaration in the Oval Office.
From CNN's Jeremy Diamond
President Donald Trump defended his decision to pull funds from the Department of Defense military construction budget in order to build a border wall, claiming that "some of the generals think this is more important."
Trump also touted the fact that he's increased the military budget in recent years.
President Trump said he'll sign the final paper work to declare a national emergency to fund his wall as soon as he gets back to his office — and he's already anticipating a legal challenge.
After he signs national emergency and executive action paperwork, Trump said, "We will then be sued," rattling off a possible chain of events, which included bad ruling in the 9th Circuit Court, which he has previously lamented.
"We will possibly get another bad ruling, and then we’ll get another bad ruling, and then we’ll end up in the Supreme Court," Trump said, comparing the process to challenges to his administration's travel ban.
"And then, hopefully, we'll get a fair shake."
What this is about: There has been speculation that Democrats or landowners on the Souther border would sue if President Trump declared a national emergency to build the wall.
Speaker of the House Nancy Pelosi said just yesterday that the Democrats could take legal action.
"I may. That's an option," she told reporters Thursday.
Watch the moment:
From CNN's Jeremy Diamond
Speaking from the Rose Garden, President Trump confirmed he will declare a national emergency in order to secure funding to build a wall at the southern border.
He argued that his actions are consistent with those of his predecessors.
"I'm going to be signing a national emergency, and it’s been signed many times before. It’s been signed by other presidents from 1977 or so it gave the presidents the power," Trump said. "There’s rarely been a problem. They sign it, nobody cares. I guess they weren’t very exciting."
The President argued that he is doing so to address "an invasion of our country with drugs, with human traffickers, with all types of criminals and gangs."
"We don’t control our own border," Trump said. "We’re going to confront the national security crisis on our southern border and we’re going to do it – one way or the other we have to do it."
Trump went on to repeat his past talking points about "tremendous amounts of drugs" crossing into the US from the southern border -- even though the majority of those drugs come through ports of entry -- and addressed the issue of human trafficking.
He once again reiterated his claim that El Paso is safer because of the border fencing, despite statistics showing violent crime rates did not go down as a result of the construction of fencing there.
Watch the moment:
As Trump launched into his immigration speech at the Rose Garden, he pledged action against "the national security crisis on our southern border."
"We are going to do it one way or the other. We have to do it. Not just because it was a campaign promise -- which it is."
He then decried the "drugs flowing into our country" through the southern border, and accused Democrats of lying about drugs entering through ports of entry.
"They go through areas where you have no wall. Everybody knows that. Nancy knows it. Chuck knows it. They all know it. It's all a big lie. It's a big con game," he said, referring to House Speaker Nancy Pelosi and Senate minority leader Chuck Schumer.
Some context: In describing the effectiveness of the wall, Trump brought up El Paso, Texas, where he held a rally Monday night. He described the border town's crime rate decreasing since the construction of a border fence — a familiar but inaccurate claim. Violent crime had actually been falling a full decade before the fence was built.
President Trump just began speaking at the White House. The White House said his remarks would be about "the National Security and Humanitarian Crisis on the Southern Border," and we're expecting Trump to declare a national emergency in order to fund his border wall.
But he started his speech by talking about a variety of other issues. Here's a look:
From CNN's Jeremy Diamond
White House chief of staff Mick Mulvaney said President Donald Trump is declaring a national emergency because Congress is "simply incapable of providing the amount of money necessary in the President's eyes" to secure the southern border.
"We’ve been through a shutdown. We’ve now been through 3 weeks of allowing Congress to try and work their will and they’re simply incapable of providing the amount of money necessary in the President’s eyes to address the current situation at the border," Mulvaney said.
Mulvaney confirmed CNN's reporting from Thursday evening on the breakdown in the funding, with additional money being drawn from the Homeland Security appropriations bill, the Treasury Department's drug forfeiture fund and the Defense Department.
The latter requires the national emergency.
Mulvaney emphasized that the President will NOT be drawing on disaster relief funding for Texas or Puerto Rico.
While Trump initially planned to sign the funding bill during his Rose Garden event, Mulvaney said that is now scheduled to take place "probably later today or tomorrow" because the White House is still waiting to receive the bill from the Senate.
Mulvaney also rejected the argument that Trump's action sets a bad precedent by using his national emergency powers.
"It actually creates zero precedent," Mulvaney said, arguing Trump is using authority given to him by Congress. "This is authority given to the President in law already."
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