The US Supreme Court has given the go-ahead for Donald Trump to spend $ 2.5bn (£2bn) to build a section of wall on the southern border with Mexico.
The lower courts had frozen the cash but the court ruled by five votes to four that the US president will be able to progress with what was a major 2016 election campaign promise.
Mr 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 decision means wall projects can now begin in Arizona, California and New Mexico.
The case the supreme court ruled in began after the 35-day partial government shutdown that started last December.
Mr Trump ended the shutdown in February after Congress gave him approximately $ 1.4bn (£1.1bn) in border wall funding.
The amount was far less than the $ 5.7bn (£4.6bn) he was looking for and Mr Trump then declared a national emergency to take cash from other government accounts to use to construct sections of wall.
The money the president identified includes $ 3.6bn (£290bn) from military construction funds, $ 2.5bn (£2bn) in defence department money and $ 600m (£484m) from the treasury department’s asset forfeiture fund.
The case before the supreme court involved just the $ 2.5bn (£2bn) in defence department funds, which the administration says will be used to construct more than 100 miles of fencing.
Alexei Woltornist, a spokesman for the justice department, said: “We are pleased that the supreme court recognised that the lower courts should not have halted construction of walls on the southern border.
“We will continue to vigorously defend the administration’s efforts to protect our nation.”
House Speaker Nancy Pelosi accused Mr 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.”