Officials from both countries, meeting in Washington, agreed to keep talking on Friday.
Despite a wave of optimism, United States and Cuban negotiators meeting in Washington on Thursday could not reach an accord on re-establishing long-fractured diplomatic ties but agreed to keep talking on Friday.
Representatives from both nations met all day at the State Department to resolve a checklist of issues before they could elevate their current diplomatic outposts known as “interests sections” into full-fledged embassies and exchange ambassadors for the first time in more than half a century.
American and Cuban officials would not discuss the talks, but a State Department notice suggested officials would speak to the news media after Friday’s round.
In recent days, diplomats on both sides had said they believed an agreement was near, while noting they still had certain issues to resolve.
The United States has been insisting on assurances that its diplomats could move around Cuba freely and speak to whomever they wish, which the Cuban government often interprets as a way to strengthen the dissident movement.
The Americans also wanted guarantees that Cubans visiting the embassy in Havana would not be harassed by the police guarding it and that diplomatic shipments would not be subjected to tampering.
Cuba had been slow to agree to full diplomatic relations until it found a bank willing to handle its accounts in the United States and until it was removed from the American government’s list of states that sponsor international terrorism.
This week, American officials said Cuba had found a bank and next week, it officially comes off the terrorism list, an order President Obama made last month but required a 45-day review period to take effect.
This fourth round of talks — by Cuba’s count, it is the third, so clearly they do not agree on even small issues — took place five months after the United States and Cuba vowed to restore full diplomatic relations ruptured more than five decades ago during the Cold War.
Mr. Obama and President Raúl Castro of Cuba have publicly said they wanted embassies, but working out the details has been taking some time.
The United States broke relations with Cuba during the last days of the Eisenhower administration, on Jan. 3, 1961, growing concerned about a Communist beachhead 90 miles from its shores. The move came after Fidel Castro ordered a drastic reduction in the staff of the American Embassy, which he considered a spy outpost that was part of a plot to topple him.
Since 1977, during a period of somewhat warmer relations, the two nations agreed to open interest sections in their capitals, with no ambassadors and limited diplomatic activity and technically run under the auspices of the Swiss government.
New York Times | By RANDAL C. ARCHIBOLD