UN human rights chief Navi Pillay hopes Cuba's move to release 52 political prisoners represents "the start of significant steps" to protect human rights in the country, her spokesman said Friday.

The High Commissioner for Human Rights welcomed "with some relief" Cuban dissident Guillermo Farinas's decision to end a hunger strike after 135 days as a result of the "positive development", spokesman Rupert Colville said.

"The High Commissioner welcomes the announcement that Cuba plans to release 52 political detainees and it will particularly be good news when the phased release of all 52 has actually been completed," he told journalists.

"We hope that this will be the start of a series of significant steps to advance the protection of human rights in Cuba," Colville added.

Cuba late Wednesday agreed to free 52 political prisoners in a surprise church-state deal promising the biggest such release since President Raul Castro formally took power in the communist country in 2008.

Foreign observers lauded the announcement, with some, including the United States and Spain, providing offers of asylum.

UN human rights experts have repeatedly voiced concern about the plight of dissidents in Cuba and their imprisonment.

Last month, the UN Special Rapporteur on Torture, Manfred Nowak, said the Cuban government had failed to agree on a date to allow him to undertake a mission to the country.

Cuba had invited Nowak in February 2009 to make what would be an unprecedented visit by a UN torture watchdog, but repeated proposals made by Nowak for dates were rejected by Havana.