Cuban state TV has shown video of Fidel Castro recovering from his operation in the company of his brother Raul and Hugo Chavez of Venezuela.
Lying in bed, the Cuban president smiles and shakes hands with Mr Chavez, a close ally, as they celebrate his 80th birthday.
The state newspaper Granma earlier published still photos of the meeting.
Their authenticity had been questioned by White House spokesman Tony Snow and Cuban exile leaders in Miami.
Fidel Castro underwent intestinal surgery two weeks ago.
His brother, 75, has temporarily taken over his presidential duties.
Granma called the bedside visit "Three Hours of Emotional Exchange".
Gifts were exchanged during Hugo Chavez's visit
The photos show gifts being exchanged and the two leaders eating what Granma called a "frugal snack".
The accompanying story quoted Mr Chavez - one of Mr Castro's closest political allies - as saying: "This is the best visit I've ever had in my life."
He is reported to have expressed admiration for the Cuban leader's stamina, saying: "What kind of human being is this? What material is he made of?"
The Venezuelan leader is quoted as saying that Mr Castro is made of caguairan - likening Cuba's revolutionary leader to a sturdy tropical hardwood tree.
Earlier Raul Castro made his first public appearance since taking over, welcoming Mr Chavez to Havana.
Official celebrations to mark Fidel Castro's 80th birthday on Sunday were cancelled but a giant concert was held in the Cuban capital, Havana, on Saturday.
On Sunday, Mr Castro also released a statement, saying his health had improved considerably but warning that his recovery would not be quick.
"I ask you all to be optimistic and at the same time to be ready to face any adverse news," the statement said.
He thanked Cubans for their loving support and said he "felt very happy" on his birthday.
Immediately after surgery, Mr Castro asked for his birthday celebrations to be postponed.
But hundreds of people attended a huge concert on Saturday, held outside the US Interests Section in Havana and lasting all night.
Mr Castro became Cuban president 47 years ago after leading the overthrow of Fulgencio Batista.
He is one of the world's longest-ruling leaders, and has outlasted nine US presidents.