The United States on Tuesday urged Cuba to end internet restrictions imposed after unprecedented protests and renewed a call for the release of detained demonstrators.

"We call on Cuba's leaders to demonstrate restraint (and) urge respect for the voice of the people by opening all means of communication, both online and offline," State Department spokesman Ned Price told reporters.

"Shutting down technology, shutting down information pathways, that does nothing to address the legitimate needs and aspirations of the Cuban people," Price said.

"We commend the people of Cuba for showing great bravery," Price said, adding that Havana has responded by trying to "silence their voices."

"We call for calm and we condemn any violence against those protesting peacefully. And we equally call on the Cuban government to release anyone detained for peaceful protest," he said.

Cuba has arrested more than 100 people including independent journalists and opposition activists after major protests in the communist-ruled island over the worst economic crisis in decades.

Web monitoring group NetBlocks reported disruptions in Cuba on major social media and communications platforms including WhatsApp and Facebook.

Cuba was quick to blame a half-century of US economic pressure for the crisis but the downturn also comes amid strict measures against Covid-19 and an uptick in cases.

Price pointed out that Cuba -- which is proud of its health care system and is rolling out an indigenous vaccine -- has not joined Covax, the UN-backed program for low-income countries to which the United States under President Joe Biden has been a major contributor.

In this file photo men ride bicycles near a poster of the late Cuban leader Fidel Castro in Havana, on July 12, 2021
In this file photo men ride bicycles near a poster of the late Cuban leader Fidel Castro in Havana, on July 12, 2021 AFP / YAMIL LAGE

"Cuba has made a sovereign decision regarding how it will address a pandemic," Price said.

"The Cuban government could always decide to receive outside vaccine donations but the Cuban government has decided not to do so yet."

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