US President Donald Trump's plans to build a border wall with Mexico moved forward on Tuesday, with the Pentagon approving billions to construct 175 miles (282 kilometers) of the border.

Defense Secretary Mark Esper approved $3.6 billion (€3.28 billion), diverting the money from 127 current military projects both inside and outside the US.

The money is being diverted from 127 current military projects both inside and outside of the US.

Esper said that the border wall projects "are necessary to support the use of the armed forces in connection with the national emergency," CNN reported, citing a letter sent to the Senate Armed Services Committee.

Trump declared a "national emergency" in February at the US southern border after lawmakers in Congress refused to approve the $5.7 billion Trump had demanded to the long-promised barrier.

Wall funds 'slap in the face' to military

The Pentagon's decision to approve the wall funds, and to pull that money from existing military projects sparked the ire of the opposition Democrats.

"It is a slap in the face to the members of the armed forces who serve our country that President Trump is willing to cannibalize already allocated military funding to boost his own ego and for a wall he promised Mexico would pay to build," Senate Democratic Leader Chuck Schumer said in a statement.

"Congress will strongly oppose any funds for new wall construction," he added.

The move puts lawmakers who blocked Trump's wall funding in a difficult position, as they must now decide if they will refund the projects that are being used to channel money to the wall.

The Trump administration secured a major win in July after the Supreme Court lifted a spending freeze on money for the wall. The American Civil Liberties Union (ACLU) said it would challenge the latest wall funding attempt in court.

rs/ng (AP, AFP, dpa)

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