The daily Granma said Maduro traveled Tuesday to Castro's tomb in Santiago de Cuba.

Maduro was accompanied by his wife Cilia Flores, Cuban President Raul Castro -- Fidel's brother -- and Cuban Foreign Minister Bruno Rodriguez, according to the newspaper.

"On the 91th birthday of the Commander in Chief a tribute by the president of Venezuela was appropriate for someone who always stood by the Bolivarian revolution," the newspaper said.

Fidel Castro, born on August 13, 1926, died in November 2016. His remains are buried at the Santa Ifigenia cemetery in Santiago de Cuba, some 960 kilometers east of Havana.

Venezuela is Cuba's most important economic and political ally, and Havana has offered strong support for Maduro's embattled leftist regime.