The elder Castro, in his first comment on the death of Mandela, touched on the handshake that made headlines around the world, at the end of a long column published in the Cuban media that praised Mandela and reviewed Cuba's role in ending apartheid.
"I congratulate Comrade Raul for his brilliant performance (at the memorial), and especially for his firmness and dignity when with a friendly but firm greeting to the head of government of the United States he said in English, 'Mr. President, I am Castro'."
The White House played down the handshake, saying it was unplanned and went no further than pleasantries.
Still, the meeting had resonance because US relations with Cuba have undergone a surprise warming in recent months with several instances of cooperation instead of the usual hostile rhetoric.
Obama said last month in Miami that it may be time for the United States to revise its policies toward Cuba, against which it has had a trade embargo for more than half a century.
Obama questioned whether the policy that was put in place in 1961 remains an effective way of dealing with US differences with the communist-ruled island nation.
Fidel Castro, 87, who was operated on in 2006 for intestinal bleeding and never fully recovered, handed over power to his brother, who is five years younger, in 2008.
Fidel Castro made no public comment on Mandela's death at the time and was too old to attend last week's ceremony in South Africa.
He has not been seen in public in months, though an official photo released on Monday showed him seated in a blue sweat suit talking with his biographer, Spanish writer Ignacio Ramonet, last week.
Fidel Castro was a leading voice against apartheid when some other world leaders were reluctant to speak out.
Mandela was deeply appreciative of Cuban support in the fight against apartheid - a conflict that included Cuban troops who fought and died in southern Angola.
Castro, in his Thursday column, complained that the roots and crimes of apartheid had been given short shrift in coverage of Mandela's death, as were his beliefs.
"It's a very real fact that Mandela was a complete man, profound revolutionary and radically socialist, who with great stoicism withstood 27 years of solitary confinement," Castro said.
"I have never ceased to admire his honesty, modesty and enormous merit."
COMMENTS
Comments are moderated and generally will be posted if they are on-topic and not abusive.
For more information, please see our Comments FAQ