Donald Trump hails ‘big victory’ as top court allows him to tap $2.5bn in Pentagon funds to build parts of border wall.

The US Supreme Court has cleared the way for President Donald Trump‘s administration to begin using billions of dollars in military funds to build parts of a border wall with Mexico.

Friday’s decision by the conservative-majority court clears the way for Trump to make progress on a major 2016 campaign promise heading into his race for a second term.

“Wow! Big VICTORY on the Wall. The United States Supreme Court overturns lower court injunction, allows Southern Border Wall to proceed. Big WIN for Border Security and the Rule of Law!” Trump said after the announcement.

The Supreme Court’s action reverses the decision of a trial court, which initially froze the funds in May, and an appeals court, which kept that freeze in place earlier this month.

The freeze had prevented the government from tapping approximately $2.5bn in Defense Department money to replace existing sections of barrier in the states of Arizona, California and New Mexico with more robust fencing.

The lawsuit at the Supreme Court was brought by the American Civil Liberties Union on behalf of the Sierra Club and Southern Border Communities Coalition. The challengers said the wall would be disruptive to the environment in part because it could worsen flooding problems and have a negative impact on wildlife.

The five justices who lifted the freeze on the money did not give a lengthy explanation for their decision.

But they said among the reasons they were doing so was that the government had made a “sufficient showing at this stage” that those bringing the lawsuit did not have a right to challenge the decision to use the money.

‘Regrettable and nonsensical’

The four liberal justices dissented, with Justice Stephen Breyer saying he would have allowed the government to finalise the contracts for the segments but not begin construction while the lawsuit proceeded.

“Today’s decision to permit the diversion of military funds for border wall construction will wall off and destroy communities, public lands, and waters in California, New Mexico, and Arizona,” said Gloria Smith, an attorney with the Sierra Club.

Trump had originally requested $5.7bn from the Congress for his border wall, but after a tug-of-war that included a record 35-day federal government shutdown, he reluctantly signed a spending bill that included appropriations of just $1.4bn for border barriers, and not specifically a wall.

Then on February 15, citing an “invasion” of drugs and criminals, he declared a national emergency at the border, allowing him to repurpose billions of dollars in other government funding. The $2.5bn in Defense Department funds at play in the Supreme Court ruling were part of that repurposed money.

Democrats said Trump’s action exceeded his powers under the US Constitution and usurped the authority of Congress.

House Speaker Nancy Pelosi issued a statement on Friday night accusing Trump of trying to “undermine our military readiness and steal from our men and women in uniform to waste billions on a wasteful, ineffective wall that Congress on a bipartisan basis has repeatedly refused to fund”.

She said the Supreme Court’s decision “undermines the constitution and the law”.

Senate Democratic Leader Chuck Schumer of New York called the decision “deeply regrettable and nonsensical”.

Claire Finkelstein, Director of the Centre for Ethics and the Rule of Law at the University of Pennsylvania Law School, said the Supreme Court’s ruling was a symbolic gesture to support Trump.

“The taxpayer is going to pay for this. The funds are being diverted from other military necessities,” said Finkelstein.

“This is such a small proportion of the funds that are necessary to build this wall that it is really a symbolic gesture on the part of the Supreme Court supporting Donald Trump’s authority as commander-in-chief of the armed forces.”

The Supreme Court victory was the second piece of good news for Trump, who earlier on Friday announced that a “landmark” asylum agreement had been reached with Guatemala, which Trump claimed would classify the Central American nation as a “safe third country”, meaning that US-bound migrants who entered the country would be required to seek asylum there instead.

The Guatemalan government said the deal would apply to citizens from Honduras and El Salvador. It did not say whether it had signed a safe third country agreement.