The comments coincide with the one-year anniversary of an agreement between the United States and Cuba marking the restoration of diplomatic relations between the two countries after over 50 years of American sanctions on the formerly Communist-led island nation.
"We do hope to achieve a successful outcome of these negotiations very, very soon. It would be wrong of me to pinpoint exactly when, but we certainly hope before the end of the year, if not sooner," said the official, who agreed to speak on condition of anonymity.
Three months ago, a DoS official stressed that safety and security were among key civil aviation issues being discussed.
US Ambassador in Havana Jeffrey DeLaurentis echoed the anonymous official in describing the resumption of commercial flights between the two countries.
"We have made good progress and come a long way," DeLaurentis told reporters.
American-Cuban relations are at a very positive point, although sensitive issues remain on the diplomatic agenda, including the Gitmo detention facility and limited financial operations linked to the trade embargo. The two countries have normalized diplomatic relations, established postal exchange, held claims discussions, and streamlined data exchange.