Cuba has reportedly demanded the Guantanamo Bay military base back from the United States before diplomatic relations are normalised with Washington.
The two nations announced a historic thaw in relations, ending five-decade-long political standoff between the two, reported the BBC.
President Raul Castro called for lifting the U.S. trade embargo and the removal of Cuba from a terror list.
High-level talks were concluded last week.
Meanwhile, a Congressional delegation arrived in Havana to start negotiations aimed at reopening embassies in the two countries' capitals.