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By Enrique Andres Pretel
CARACAS, Feb 27 (Reuters) - Cuban leader Fidel Castro said on Tuesday he was recovering and feeling stronger in his first live radio broadcast since emergency stomach surgery forced him to relinquish power in July.
Sounding much healthier and more lucid than he has in taped video clips released during his convalescence, Castro laughed frequently in a half-hour chat with Venezuelan President Hugo Chavez that was marked by boyish humor.
"I am gaining ground. I feel I have more energy, more strength, more time to study," he said on his top ally’s nightly call-in radio show, which was later played on Cuban state television.
"I have become a student again," Castro added with a chuckle.
His guest appearance came as a surprise to listeners. Chavez said his energy minister was on the line but the 80-year-old Cuban’s voice broke in: "Listen, my distinguished and dear friend, how are you?"
"Goodness, it’s Fidel," Chavez replied.
Then the two icons of Latin America’s left, who pride themselves on their anti-Americanism, exchanged pleasantries -- in English.
"Fidel, how are you?" Chavez said with a heavy accent.
"Very well," Castro replied as they both laughed.
Castro later commented on the fall of world stock markets on Tuesday, the worst in years, and said it was proof of his view that capitalism was in crisis.
Chavez calls Castro his mentor and has frequently visited him during his convalescence, with images of the meetings broadcast afterward.
A video clip of their last meeting released almost a month ago showed Castro had put on weight but remained frail. Castro has not been seen in public since the surgery.
In power since 1959, Castro handed over control temporarily to his brother, Defense Minister Raul Castro, on July 31.
Castro’s condition is a tightly guarded state secret. His illness was officially attributed to the "extreme stress" of his workload.
Cuba watchers say Castro’s backstage presence and the carefully staged meetings with Chavez could be reassuring to Cubans and help his successors maintain the one-party state.
The conversation with Chavez on Tuesday was broadcast by Cuban state television, where presenters looked overjoyed. It was the first time Cubans had heard Castro speak in a live broadcast since his last public appearance at a rally on July 26.
Castro and Chavez touched on political and economic topics such as producing ethanol as an energy source and Venezuela’s industrial output.
When Chavez told Castro he planned to visit fellow leftist presidents in Bolivia and Argentina next week, the Cuban leader replied lightheartedly, "I cannot promise I‘m going to accompany you on one of those trips."
Chavez ended the call, saying, "I declare to the world that you are my father." Castro signed out with the revolutionary slogan, "We will overcome."
(Additional reporting by Anthony Boadle in Havana)