(AFP) - Cubans voted overwhelmingly in favor of constitutional reforms that cement the role of socialism in the island nation, the electoral commission said Monday.

Some 6.8 million people, or more than 86 percent of voters, supported the changes in Sunday's referendum, while only 766,400, or nine percent, voted against.

A total of 7.8 million people took part in the vote, with just over four percent of ballots blank or invalid.

"The constitution has been ratified by the majority of citizens," electoral commission president Alina Balseiro told a news conference.

"Cubans have said #YesForCuba and #YesForTheRevolution," Foreign Minister Bruno Rodriguez tweeted.

"It's an overwhelming response to the unbelievers who from Washington talked about the end of #Socialism, with policies that failed for more than 60 years.

"#Cuba keeps going, always free, revolutionary and socialist."

US President Donald Trump had said earlier this month that the leftist ideology is "dying."

But academic and former diplomat Carlos Alzugaray had told AFP that Trump's words would serve only to galvanize the "yes" vote as people "defend their independence against the US threat."

The constitutional reforms ratify socialism's "irrevocable" role as the national ideology and replaces the 1976 constitution, a move criticized by the Catholic and evangelical churches.

It also recognized the Communist Party as the "superior ruling political force in society and the State," and its position as the nation's only party.

- Campaign for 'no' vote -

It has ruled Cuba since 1959, first under revolutionary hero Fidel Castro, then his brother Raul and, since April, Miguel Diaz-Canel.

The reforms do, however, recognize a limited role for the free market and private investment, but only under Communist Party control.

Cuba's outlawed opposition had campaigned hard on social media for a "no" vote.

Normally, it pushes for abstention, but this was a rare opportunity to vote "no" to the one-party communist regime.

The "yes" campaign benefited from omnipresence in the media, which is controlled by the state, as well as in public spaces.

The government only needed a simple majority for the reforms to pass and had portrayed a 'no' vote as unpatriotic.

The text of the reforms had undergone extensive public debate between August and November, with several changes made before the final version was submitted to the referendum.

Before becoming official, the reforms must be proclaimed by the National Assembly, probably during a session in April, and then published by the Official Gazette.

Authorities said more than 84 percent of registered voters cast ballots, but the victory margin was tighter than Cuba is used to.

The 1976 constitution, for example, received 97.7 percent support.

"The country has changed and it's a different constitution with more complications," Alzugaray said.

© Agence France-Presse