The result of the votes for president and vice-presidents and other national leaders is expected to be officially announced Thursday, the anniversary of the USA -backed Bay of Pigs invasion defeated by Cuban forces in 1961.
In an unusual two-day procedure, the legislature will choose a new president on Wednesday and announce the replacement for Raul Castro on Thursday.
Facing biological reality but still active and apparently healthy, Raul Castro is stepping down as president in an effort to guarantee that new leaders can maintain the government's grip on power in the face of economic stagnation, an aging population and increasing disenchantment among younger generations.
Diaz-Canel, born after the revolution, embraces technology and appears socially liberal.
Nominated as new first vice-president was Salvador Valdes Mesa, a 72-year-old Afro-Cuban former union official who has held a long series of high posts in the Cuban government. She entered politics when she was 16.
Cuba's new National Assembly (single-house parliament) gathered on Wednesday for its first session at Havana's Palace of Congresses for electing a successor of the current president of the country's State Council, Raul Castro.
The nomination must be approved by the Cuban National Assembly, which has historically approved nominations. And after serving for a decade as president, Raul Castro, 86, announced earlier this year that he will remain the first secretary of the Communist party until 2021.
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A witness recorded the attack on their cell phone and shared it with the victim, investigators said. Police then learned that Allison was allegedly responsible for the robbery on Elderank Drive.
The accounts are using the hashtag "Somos Continuidad" or "We are continuity".
But with the economy suffering from a crisis in allied Venezuela and relations with the United States strained anew under President Donald Trump, some Cubans are pessimistic about their lives improving and feel nervous about what is to come.
Internet access has increased dramatically over the past two years but the country still has one of the lowest percentages of home internet usage in the world.
Cuba's legislature has opened a two-day session that is to elect a successor to President Raul Castro.
The men who have run Cuba for almost six decades began life in a remote, rural part of the island known as Biran, sons of a wealthy farmer. On Jan. 1, 1959, Batista fled and Fidel Castro became the unquestioned leader of Cuba, with his younger brother put in charge of the armed forces.
Cuban Vice President Miguel Diaz-Canel arrives for a welcome ceremony for then-President Barack Obama at the Palacio de la Revolucion in Havana, March 21, 2016.