Venezuelan President Hugo Chavez has shown a letter from Fidel Castro which he says is proof that the ailing Cuban president is recovering.
Mr Chavez drew attention to Mr Castro's firm handwriting, saying: "This is for those who say he's dying."
The letter was delivered by Cuban Vice-President Carlos Lage who had told him Mr Castro was now up and walking.
The Cuban leader's condition has been the subject of much speculation since he underwent gastric surgery last July.
The 80-year-old's health is treated as a state secret in Cuba
Earlier this month, President Chavez refuted a report in a Spanish newspaper that said Mr Castro's prognosis was very grave after three failed operations.
But last week, Mr Chavez said Fidel was ''battling for his life''.
Speaking in the Venezuelan capital, Caracas, Mr Lage said the Cuban people continued to be united and confident even though Fidel Castro is no longer in charge of presidential duties.
Fidel's younger brother Raul has been acting as president since July.
President Chavez showed the letter from Mr Castro at ceremony in Caracas where Venezuelan and Cuban officials signed several accords.
"Look closely at the strokes of the signature. We are extremely happy, Fidel, about the news of your recuperation," he said.
"Lage told me that Fidel walked I don't know how many minutes yesterday.
"He's walking more than me, almost jogging - maybe he's walking while watching us.
"We will have Fidel and we will have Raul for a lot more time," Mr Chavez said.