Though Trump has pushed back congressional efforts to check his declaration for now, his administration still has to fight court challenges. More than a dozen states and several outside groups have filed lawsuits challenging his executive action.

"Congress has the freedom to pass this resolution, and I have the duty to veto it," he said before he rejected what he called a "reckless resolution." The president added that he "put no pressure on anybody" to vote against the legislation "because we all knew it was going to be a veto."

The GOP-controlled Senate dealt a blow to Trump on Thursday, when 12 Republicans joined with Democrats in voting to terminate his emergency declaration. He publicly pushed Senate Republicans to vote against the House-passed resolution even as he shot down one plan that could have limited the number of GOP senators voting to block his flex of executive power.

The president's veto, signed in front of reporters in the Oval Office, is his first since he entered the White House. While the Democratic-held House will try to override his opposition, neither chamber of Congress appears to have enough support to reach the two-thirds majority needed.

President Donald Trump rejected a bill Friday that would end the national emergency he declared at the southern U.S. border.

President Donald Trump speaks about border security in the Oval Office of the White House, Friday, March 15, 2019, in Washington. Trump issued the first veto of his presidency, overruling Congress to protect his emergency declaration for border wall funding.

Those lawsuits in part cited comments Trump made when he declared the emergency last month. The president said he "didn't need to" take that step but wanted to expedite the construction of barriers.

Democrats plan to vote to override Trump's veto on March 26, House Speaker Nancy Pelosi said in a written statement Friday. When the House voted on it previously, 245 members supported it, well short of the 285 needed for two-thirds support. (The House currently only has 432 members due to three vacancies.)

"On March 26, the House will once again act to protect our Constitution and our democracy from the President's emergency declaration by holding a vote to override his veto," the California Democrat said. "House Republicans will have to choose between their partisan hypocrisy and their sacred oath to support and defend the Constitution."

Rep. Joaquin Castro, a Texas Democrat who introduced the measure to block the declaration in the House, said Thursday that he will try to gather support for another vote even though it will be "very tough" to reach a two-thirds majority.

Trump declared a national emergency at the U.S.-Mexico border last month to divert already appropriated Defense Department money to build his proposed border wall. He demanded $5.7 billion for border barriers as part of a spending plan to fund the government through September, but Congress denied him. Lawmakers passed only $1.4 billion for structures on the border.

Democrats said Trump created a sham emergency in order to circumvent Congress' appropriations power. Republicans also worried the president is setting a dangerous precedent that Democrats could use in the future to declare emergencies related to other topics such as climate change and gun violence.

"It is no surprise that the president holds the rule of law and our Constitution in minimal regard," Senate Minority Leader Chuck Schumer, D-N.Y., said in a statement following the veto. "There is no emergency; Congress has refused to fund his wall multiple times; Mexico won't pay for it; and a bipartisan majority in both chambers just voted to terminate his fake emergency."

Trump hopes to put $8 billion total toward the border wall, including the money allocated by Congress. Using emergency powers, he would divert $3.6 billion from military construction funds. With other executive actions, he hopes to pull the remainder from other Pentagon and Treasury Department funds.

The wall will not go away as a political issue. Trump set up another fight with Democrats when he asked for an additional $8.6 billion for border barriers in his recently released fiscal 2020 budget.

Democrats could also vote on whether to block the national emergency declaration every six months.

The Senate rebuked Trump twice this week. The chamber also voted to end U.S. support for a Saudi-led coalition's military intervention in Yemen. Once the House passes the resolution, as expected, the president will likely have to issue his second veto.

Trump's two predecessors, Presidents Barack Obama and George W. Bush, both issued 12 vetoes during their two terms in office.

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