In his first live broadcast since falling ill last July, Cuban leader Fidel Castro called Venezuelan President Hugo Chavez's daily radio talk show to say he was feeling "more energetic".
Castro, 80, handed power to his brother Raul Castro, 75, in late July as he recovered from what is described as gastrointestinal surgery.
The Cuban leader, who first took power in 1959, has since only been seen in official Cuban television and newspaper images, though he has met some few visitors in Havana.
In Tuesday's phone call, Castro came across as energetic and enthusiastic as he commented on the day's news.
"Hello there, illustrious and dear friend, how are you?" Castro asked Chavez at the start of his 25-minute telephone call on the Venezuelan leader's "Hello President" show.
"What joy hearing your voice, and knowing you are well," Chavez replied.
"I am making progress, I feel more energetic, with more strength and more time to study," Castro said. "I have gone back to being a student."
The Cuban leader encouraged those concerned about his recovery to be patient.
{{/usCountry}}The Cuban leader encouraged those concerned about his recovery to be patient.
{{/usCountry}}"I urge everyone to be patient, calm, and to be happy, if everyone is calm, the country keeps moving forward, which is the important thing... I also ask for tranquility for myself to be able to get my new duties done," he said.
But "I cannot be talking every day and get into the habit of making news every day.