Cuba demanded Friday that the United States cease its "illegal and covert actions" against the communist country following disclosures Washington set up a Twitter-style application there.
The White House on Thursday acknowledged the existence of the social media scheme but denied it was secret or intended to incite political unrest against the island's leaders.
"The US government must respect international law and the purposes and principles of the United Nations Charter and therefore cease its illegal and covert actions against Cuba, which are rejected by the Cuban people and international public opinion," foreign ministry official Josefina Vidal told AFP via email.
White House spokesman Jay Carney said the program, first revealed by the Associated Press, was a "development assistance" project targeted at Cubans facing government restrictions on information.
He added it had never been covert, was debated in Congress and conducted within US law.
Vidal, however, insisted the AP report "confirms the repeated complaints by the Cuban government."
"This once again shows that the United States government has not renounced its subversive plans against Cuba," she added.
These plans "aim to create destabilizing situations in the country to bring about changes in our political system and to which (the United States) continues to devote multimillion dollar budgets every year."
The project was known as "Zunzuneo" after a Cuban term for the buzz of a hummingbird and was a platform for Cubans to "speak freely among themselves," said Matt Herrick, a spokesman for the the US Agency for International Development (USAID) that set it up.
Cuba and the United States have not had diplomatic relations since 1961. Washington has maintained an embargo on the communist country since 1962.