The White House national security adviser John Bolton called the constitutional referendum on Sunday in Cuba "another deceit" to "cover up the tyranny" of the Havana's "regime."
"Today's constitutional referendum is another deceit by the Cuban regime to cover up its repression and tyranny," Bolton said in a message on his Twitter account.
"The United States supports the calls of the Cuban people for freedom and democracy," President Donald Trump's chief national security adviser said.
Marco Rubio, a senator from Florida and former candidate for the US presidential candidacy in 2016, said that "the so-called" referendum "in Cuba is another maneuver by the Cuban dictatorship to hold on to power."
"The plebiscite of today is a farce and a fraud of the communist party of the island," Rubio also stressed in that social media.
More than eight million Cubans are called to the polls on Sunday throughout the country (11.2 million inhabitants), where more than 25,300 polling stations operate.
The new Constitution seeks to give an impression to the controlled economic opening driven by former President Raúl Castro, who succeeded Miguel Díaz-Canel in 2018 and reflect the new Cuban society, very different from the one that participated in the 1976 referendum.
The first draft of the project was submitted to three months of popular consultations in which for the first time more than 1.4 million Cubans living abroad were included, although they cannot vote in the referendum.
The text submitted to referendum this Sunday was modified by 60% compared to the initial project, after the inclusion of the proposals collected during the citizens' debates and the elimination of controversial articles such as the one that opened the door to gay marriage on the island.
The revised version again includes the term "communism," which did not appear in the initial draft; maintains the Communist Party as the "highest leading force in society;" establishes the presidential mandate in a maximum of two consecutive periods of five years and establishes a limit of 65 years to accede for the first time to the head of the State.