The former foes completed today a third round of negotiations since Presidents Barack Obama and Raul Castro announced in December their intention to improve relations.
A Cuban statement says they agreed to continue talks, but gave no date for the next round.
Many differences appear close to being resolved. Cuba comes off a US terrorism list May 29. Its Interests Section in Washington now has a U.S.-based bank account, meaning it doesn't have to operate on cash anymore.
The US wants to ensure that its diplomats can travel throughout Cuba and meet dissidents without restrictions.