The US Supreme Court has said that President Donald Trump can use $2.5bn of Pentagon funds for a section of wall on the southern border, the BBC reports.
The court ruled by five votes to four to block a ruling by a federal judge in California that barred the president from spending the money on the wall.
The wall, dividing the US and Mexico, was Mr Trump’s major campaign promise during the 2016 election.
It is fiercely opposed by Democrats.
The decision by the Supreme Court means that the money will be used for wall projects in California, Arizona and New Mexico.
The court in California had argued that Congress had not specifically authorized the funds to be used for constructing the wall.