The Cuban dictator has not been seen in public since before July 31, when he announced he had undergone surgery and provisionally ceded power to his younger brother Raul. With Cuban officials giving increasing positive reports about Fidel Castro's health, there has been speculation recently that he could soon be back in the public eye.
"Fidel is in charge. Fidel is in charge," Chavez said, revealing that he received a "philosophical letter" from Castro the day before and that it ran to nearly 10 pages.
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Speaking during a meeting of leftist leaders, Chavez laughed as he said that Bolivian President Evo Morales "is determined that Fidel will come out on May 1."
"I think that Evo and Fidel have such a secret plan that even I don't know what it is. I don't dare to make comments," Chavez said.
Since his surgery, Chavez has regularly offered updates on Castro's health, while the 80-year-old leader has appeared periodically in photographs and videos released by the Cuban government.
Castro's condition and exact ailment remain state secrets, but he is believed to suffer from diverticular disease, which can cause inflammation and bleeding in the colon.
Chavez said Castro's health troubles have clearly forced him to slow down but that he has made a "real improvement" and is in an "extraordinary mental state."
Castro's government was represented at the leftist leaders' summit by Cuba's Vice President Carlos Lage.
"For eight months he has been fighting for his own life," Lage said of Castro. "Today we can tell you that Fidel has won the fight for his life ... and now he is consolidating the victory, and for that reason he hasn't been present here as all of us would have wanted."
Lage and Chavez both said Castro has continued to play an active role behind-the-scenes.
Earlier, Chavez held a letter from Castro up for television cameras, showing a firm signature that he called a clear sign of the Cuban leader's improving heath.
"Fidel does impossible things," Chavez said.
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