"At 10:29 in the night, the chief commander of the Cuban revolution, Fidel Castro Ruz, died," he said.
"Ever onward, to victory."
Castro had been in failing health for years, and was the subject of death rumors for nearly as long.
His cause of death was immediately unclear.
Cuba declared nine days of national mourning as people took to the streets in Little Havana, Miami to celebrate the late Cuban revolutionary's death on Friday night.
Carlos A. Gimenez, mayor of Miami-Dade county, tweeted on Saturday that Castro's passing "closes a very painful chapter for Cubans on the island and Cuban-Americans throughout the world."
(People celebrate the death of Cuban leader Fidel Castro, in Little Havana, Miami, Florida, U.S. November 26, 2016.Reuters)
Fidel Castro was born Fidel Alejandro Castro Ruz on August 13, 1926, in the small eastern village of Biran. His father was a wealthy sugarcane farmer; his mother worked as a maid to his father’s first wife.
Castro received a Roman Catholic education through high school. He later excelled as an athlete and went on to law school at the University of Havana, where he would find an interest in politics.
A more radical bent soon emerged, as Castro plotted and executed several attempts at overthrowing Cuban leaders and making an attempt at a bid for Cuba's House of Representatives. Following a series of offensives, he seized power in 1959 from Cuban dictator Fulgencio Batista. He did not look back.
Though he was admired by leftists worldwide, Castro was demonized by the US and many of its allies.
Once in power, Fidel Castro moved quickly to nationalize businesses across the island, moving away from the US and toward the Soviet Union. The US officially cut all diplomatic ties with Cuba in January 1961.
Fabian Escalante, who served as the head of Cuba's intelligence services and was tasked with protecting Castro for much of his career, estimated that the CIA and Cuban exiles had made 638 attempts on Castro's life by the time he surrendered power to his brother Raul in 2006, after 47 years of rule.
(Fidel Castro.JFK Library) Some extended condolences to Cuba over Castro's death, including Evo Morales
"With the death of Fidel Castro, the world has lost a man who was a hero for many," Juncker tweeted on Saturday.
China's president, Xi Jinping, said in a televised statement on Saturday that "the Chinese people have lost a good and true comrade. Comrade Castro will live forever."
China is one of the world's few remaining communist states.
(China's president, Xi Jinping, mourned Castro's death on Saturday, saying that "the Chinese people have lost a good and true comrade."Reuters/Jason Lee)
To many exiles awaiting Castro's death, however, the late revolutionary embodied a heavy-handed regime that jailed political opponents, suppressed civil liberties, and wrecked the island's economy.
Florida senator Marco Rubio, a Cuban-American whose parents left Cuba in 1956, released a statement Saturday morning saying that "history will not absolve Fidel Castro."
"His communist regime turned [Cuba] into an impoverished land prison," Rubio wrote. "Over six decades, millions of Cubans were forced to flee their own country, and those accused of opposing the regime were routinely jailed and even killed."
Rubio added that "sadly, Fidel Castro's death does not mean freedom for the Cuban people...the dictator has died, but the dictatorship has not."
(Raul Castro took over from his brother, Fidel, in 2006.) Cuba is still being ruled by Castro's brother, Raul.
Texas senator Ted Cruz, whose father fled Cuba in 1957, wrote on Facebook that "Fidel Castro's death cannot bring back his thousands of victims, nor can it bring comfort to their families. Today we remember them and honor the brave souls who fought the lonely fight against the brutal Communist dictatorship he imposed on Cuba."
President-elect Donald Trump tweeted on Saturday morning, "Fidel Castro is dead!"
US President Barack Obama has not yet released an official statement on Castro's death.
Cuba's insular policies began to thaw a bit in 1998, when Pope John Paul II became the first pontiff to visit the nation. Pope Benedict would follow more than a decade later.
In 2003, Castro was confirmed as president for another five-year term. Then in the waning years of his rule, Castro oversaw several initiatives that led to a major crackdown on independent journalists, dissidents and activists, and a strengthening of ties with Venezuela.
The Bolivarian Alternative for the Americas was birthed from that, in which Cuba sent health professionals to Venezuela in return for discounted oil.
(Cuban leader Fidel Castro looks out over a 3,000 stong crowd that screaming "Fidel, Fidel," in a concert hall were left-wing groups were holding a rally against the UN summit for Social Development in Copenhagen.Reuters/FOR P-BASE- FILE PH0TO)
By 2006, Castro handed provisional control of Cuba to his brother, Raul, while Fidel reportedly recovered from a major intestinal surgery. That was the first time he surrendered control of his power in 47 years.
He did not return.
In 2008, when the National Assembly prepared to reconfirm Fidel as Cuba’s leader, he declined in a letter.
At that point, he hadn’t been seen publicly for nearly two years.
The letter was posted to the Communist Party’s website Granma, in which Castro said, “I do not bid you farewell. My only wish is to fight as a soldier of ideas.”
Castro made several more public appearances in 2010, but officially stepped down from the Communist Party of Cuba in 2011, leaving the younger Raul Castro to introduce possibly the most significant change in Cuba since the 1960s, announcing a deal with the Obama administration to reinstate diplomatic ties with the US in 2014.