U.S. and Cuban officials held a brief technical-level meeting Tuesday to define an agenda for future sessions on human rights as part of the rapprochement between the long-time adversaries, a Cuban source said.

The source, who spoke on condition of anonymity, provided no details on the substance of the talks.

The State Department, which hosted them, had previously described them as "preliminary" in nature and devoted to discussions about the modalities and structure of future conversations on human rights.

The two countries have held a series of talks since U.S. President Barack Obama and Cuba's President Raul Castro decided in December to work to restore relations severed more than 50 years ago.