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

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 likely try to override his opposition, neither chamber of Congress appears to have enough support to reach the two-thirds majority needed.

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.

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