The popular social media platform missed a court-imposed deadline on Thursday evening to name a legal representative in Brazil, triggering the suspension.
Musk has argued that Supreme Court Justice Alexandre de Moraes was trying to enforce unjustified censorship, while the judge has insisted that social media needs hate speech regulations.
"They’re shutting down the #1 source of truth in Brazil," Musk said in a post on X on Friday.
The judge’s ruling could cause X to lose one of its largest and most coveted markets, at a time when Musk has struggled with advertising revenue for the platform.
X remained accessible in Brazil late on Friday, though some Brazilians posted on other platforms that their access to X was already being blocked. Three of the country’s top telecommunications carriers said they would begin blocking access from midnight (0300 GMT on Saturday), according to a report by local news outlet UOL.
The feud has led to the freezing this week of satellite internet provider Starlink’s bank accounts in Brazil. Starlink is a unit of Musk-led rocket company SpaceX.
In his ruling, Moraes ordered that X, formerly Twitter, be suspended in Brazil until it complied with all related court orders, including the payment of more than $3 million in fines, as well as the designation of a local representative, as required by Brazilian law.
Moraes also ordered telecommunications regulator Anatel to implement the suspension order.
The agency told Reuters it is proceeding with compliance, but without specifying a timetable.
To effectively close X in Brazil, telecommunication companies will need to stop carrying the network’s traffic, while also preventing users of the site from dodging it by concealing their locations with virtual private networks, or VPNs.
Moraes ordered that those who continued to access X via VPNs be fined up to 50,000 reais ($9,000) per day.
Tech giants Apple (AAPL.O), opens new tab and Alphabet’s Google (GOOGL.O), opens new tab were initially instructed to remove X from their app stores and implement so-called anti-VPN obstacles that would make it more difficult for users of Apple’s iOS operating system and Google’s Android to open the X app on phones or tablets.
But Moraes later reversed that part of his order, saying it would not be needed.
Press offices for Apple and Google declined to comment.
LAPDOGS AND DICTATORS?
Unlike in many other countries, Brazil’s Supreme Court judges are able to exercise sweeping powers to make unilateral decisions. But in the dispute over X, Moraes has been backed by a majority of the 11-member court, including Chief Justice Roberto Barroso.
Musk, in addition to owning X and 40% of SpaceX, is the CEO of electric vehicle giant Tesla (TSLA.O), opens new tab.
The dispute over X has its roots in a Moraes order from earlier this year that required the platform to block accounts implicated in probes of alleged spreading of distorted news and hate.
Musk denounced the order as censorship. He responded by closing the company’s offices in Brazil but ensured the platform was still available in the country.
He has said Starlink would continue to serve Brazilians, including the military, for free "until this matter is resolved."
Earlier on Friday, Starlink asked the Supreme Court to suspend its decision to freeze its local bank accounts, arguing it has complied with all judicial orders. That request was dismissed on Friday evening.
Asked to comment, Brazil s President Luiz Inacio Lula da Silva insisted that all businesses operating in the country must comply with their legal obligations.
"Just because a guy has a lot of money doesn t mean he can disrespect" the law, the leftist leader told local radio on Friday.
Musk derided the president as Moraes’ "lapdog" in a Thursday post in which he also called the judge a "dictator."
At an event on Friday, Moraes showed no signs of backing down.
"Those who violate democracy, who violate fundamental human rights, whether in person or through social media, must be held accountable," he said.