The Republican president’s move to circumvent Congress represented a new approach to making good on a 2016 presidential campaign pledge to halt the flow of undocumented immigrants into the country, whom Trump says bring crime and drugs.
He was also expected later on Friday to sign a bipartisan government spending bill Congress approved on Thursday that would prevent another partial government shutdown by funding several agencies that otherwise would have closed on Saturday.
Trump made no direct mention in rambling Rose Garden comments of the funding bill. It represents a legislative defeat for him since it contains no money for his proposed wall - the focus of weeks of conflict between him and Democrats in Congress.
Trump had demanded that Congress provide him with $5.7 billion in wall funding as part of legislation to fund the agencies. That triggered a historic, 35-day December-January government shutdown that hurt the U.S. economy and his opinion poll numbers.
By reorienting his quest for wall funding toward a legally uncertain strategy based on declaring a national emergency, Trump risks plunging into a lengthy legislative and legal battle with Democrats and dividing his fellow Republicans.
Fifteen Democrats in the Republican-controlled Senate introduced legislation on Thursday to prevent Trump from invoking emergency powers to transfer funds to his wall from accounts Congress has already committed to other projects.
Nancy Pelosi, the Democratic speaker of the House of Representatives, and top Senate Democrat Chuck Schumer swiftly responded to Trump’s declaration.
“The president’s actions clearly violate the Congress’s exclusive power of the purse, which our Founders enshrined in the Constitution,” they said in a statement. “The Congress will defend our constitutional authorities in the Congress, in the courts, and in the public, using every remedy available.”
New York state’s attorney general, Letitia James, said her office would also challenge Trump in court.
“We won’t stand for this abuse of power & will fight back with every legal tool at our disposal,” James wrote on Twitter.
The president acknowledged that his order would face a lengthy court fight.
“I expect to be sued. I shouldn’t be sued ... We’ll win in the Supreme Court,” Trump predicted.