President Trump on Thursday renewed a state of emergency he declared on the Southern border, which he has used to reprogram billions of dollars to building his border wall.

"The ongoing border security and humanitarian crisis at the southern border of the United States continues to threaten our national security, including the security of the American people," he wrote in a notice to Congress.

"The executive branch has taken steps to address the crisis, but further action is needed to address the humanitarian crisis and to control unlawful migration and the flow of narcotics and criminals across the southern border of the United States," he continued.

Trump officially declared the emergency on Feb. 15 last year after a five-week government shutdown - the longest in the nation's history - failed to convince Congress to fund the wall to his satisfaction.

The emergency powers allowed Trump to reprogram funds from military construction and other defense funds, but were set to expire on Saturday. Trump's notice will extend the powers for another year.

The notice comes just hours after reports surfaced that Trump was moving an additional $3.8 billion in defense funds toward building the wall. Those funds came from aircraft, ship-building and National Guard funds.

Democrats were outraged by the move.

"Congress has repeatedly voted in a bipartisan way to refuse funding the President's wasteful, ineffective border wall," House Speaker Nancy Pelosi (D-Calif.) and Senate Minority Leader Charles Schumer (D-N.Y.) said in a joint statement.

"This latest effort to steal Congressionally-appropriated military funding undermines our national security and the separation of powers enshrined in our Constitution," they added.

Congress was unable to override Trump's veto on the two occasions that it voted to overturn the emergency. It is likely Congress will vote on the issue again.

Rep. Mac Thornberry (R-Texas), the top Republican on the House Armed Services Committee, called for renewed congressional action.

"The re-programming announced today is contrary to Congress's constitutional authority, and I believe that it requires Congress to take action," he said.

Earlier in the week, Trump dropped his annual request for congressional funding for the wall to $2 billion from $5 billion in previous years, in part because he had succeeded in reprogramming the cash from other funds.

Previous transfers emptied accounts slated for military construction projects such as repairing barracks.