Supreme Court paves the way for Donald Trump to build his wall

US President Donald Trump is getting his way and will get his border wall with Mexico. Photo / Getty Images

It was one of his biggest 2016 election promises - and today it looks like it may happen, and Donald Trump isn't holding back his delight.

The US Supreme Court has cleared the way for the Trump administration to tap billions of dollars in Pentagon funds to build sections of a border wall with Mexico.

The court's five conservative justices gave the administration the green light to begin work on four contracts it has awarded using Defence Department money. Funding for the projects had been frozen by lower courts while a lawsuit over the money proceeded. The court's four liberal justices wouldn't have allowed construction to start.

A U.S. Customs and Border Protection vehicle sits near the wall as President Donald Trump visits a new section of the border wall with Mexico in El Centro, California. Photo / AP

The justices' decision to lift the freeze on the money allows President Donald Trump to make progress on a major 2016 campaign promise heading into his race for a second term. Trump tweeted after the announcement: "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!" 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 $3.7 billion in Defence Department money to replace existing sections of barrier in Arizona, California and New Mexico with more robust fencing.

The case the Supreme Court ruled in began after the 35-day partial government shutdown that started in December of last year. Trump ended the shutdown in February after Congress gave him approximately $1.4 billion in border wall funding. But the amount was far less than the $5.93 billion he was seeking, and Trump then declared a national emergency to take cash from other government accounts to use to construct sections of wall.

The money Trump identified includes $3.74 billion from military construction funds, $2.6 billion in Defence Department money and $600 million from the Treasury Department's asset forfeiture fund.

The case before the Supreme Court involved just the $2.6 billion in Defence Department funds, which the administration says will be used to construct more than 160 kilometres of fencing. One project would replace 74 kilometres of barrier in New Mexico for $821 million. Another would replace 101 kilometres in Arizona for $672 million. The other two projects in California and Arizona are smaller.

US President Donald Trump is getting his way and will get his border wall with Mexico. Photo / Getty Images

The other funds were not at issue in the case. The Treasury Department funds have so far survived legal challenges, and Customs and Border Protection has earmarked the money for work in Texas' Rio Grande Valley but has not yet awarded contracts. Transfer of the $3.7 billion in military construction funds is awaiting approval from the defence secretary.

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 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 don't have a right to challenge the decision to use the money.