HAVANA, Cuba -- The United States and Cuba have agreed to resume bilateral talks on migration issues next month, a State Department official said Wednesday, the latest evidence of a thaw in chilly relations between the Cold War enemies.

Havana and Washington just wrapped up a round of separate negotiations aimed at restarting direct mail service, which has been suspended since 1963. Both sets of talks have been on hold in recent years in a dispute over the fate of U.S. government subcontractor Alan Gross, who is serving a 15-year jail sentence in Havana after he was caught bringing communications equipment onto the island illegally.

The migration talks will be held in Washington on July 17. The State Department official, who was not authorized to discuss the matter publically, spoke on condition of anonymity.

"Representatives from the Department of State are scheduled to meet with representatives of the Cuban government to discuss migration issues," the official said, adding that the talks were "consistent with our interest in promoting greater freedoms and respect for human rights in Cuba."

Also Wednesday, Cuba issued a statement declaring the recently concluded mail talks as "welcome" and "fruitful," but also said its delegation had informed the Americans that "a high quality, stable and secure" mail service between the countries is impossible as long as Washington maintains its 51-year economic embargo on the communist-run island.

A nascent effort at rapprochement between Washington and Havana has stalled since Gross's arrest, and the resumption of the two sets of bilateral talks is sure to raise speculation that there could be movement on his case.

Gross was working on a USAID democracy building program at the time of his arrest in December 2009. Washington has said repeatedly that no major improvement in relations can occur until he is released. His family has complained that he has lost a lot of weight in jail and suffers from various ailments. Cuba reportedly has agreed to allow a U.S. doctor to visit him in detention, and has also granted him conjugal visits and made him available to high-level American delegations.

Cuba, for its part, is demanding the release of four of its intelligence agents serving long sentences in the United States. A fifth agent, Rene Gonzalez, returned home to Havana earlier this year after completing his sentence and agreeing to renounce his U.S. citizenship.

Geoff Thale, a Cuba analyst at the Washington Office on Latin America think-tank , said the resumption of talks, and the moves involving Gross and Gonzalez, are a sign that long-frozen relations could finally be improving.

"These are modest but sensible steps," he said. "What's significant is less the steps themselves than the fact that there is movement in the relationship. It's a real break from the status quo."

The migration talks are intended to monitor adherence to a 16-year-old agreement under which the United States issues 20,000 emigration visas to Cubans a year.

Separately, Cuba says it objects to an American policy known as "wet foot, dry foot" -- in which Cuban refugees reaching American soil are allowed to stay in the U.S., while those stopped at sea are sent home. Cuba says the policy encourages its citizens to try to flee the island.