The US Supreme Court has cleared the way for President Donald Trump's administration to access Pentagon funds to build sections of a border wall with Mexico.
It ruled on Friday to lift a freeze on the money put in place by a lower court.
The Supreme Court's action means the Trump administration can tap into the funds and begin work on four contracts it has awarded.
A trial court initially froze the funds in May and an appeals court kept the freeze in place earlier this month.
It had prevented the government from tapping into approximately $2.5 billion in Defense Department money to replace existing sections of barrier in Arizona, California and New Mexico with more robust fencing.
On Friday, Mr Trump tweeted that the ruling was a "victory".
He said: "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 US leader has struggled to make good on his signature 2016 campaign pledge to secure the southern border, and his policies have drawn criticism from both sides of Congress.
Legislators had expressed dismay that undocumented children were separated from their parents.
In February Mr Trump declared a national emergency in a bid to fund the wall without congressional approval, an action Democrats said exceeded his powers under the US Constitution and usurped the authority of Congress.
The administration has said it plans to redirect $6.7 billion from the Departments of Defense and Treasury toward wall construction under the emergency declaration after failing to convince Congress to provide the money, including the $2.5 billion in Pentagon funding.
