(CNN) - During their meeting at the White House last month, President Barack Obama asked Uruguay's president, Jose Mujica, to send a message to Cuban President Raul Castro to free imprisoned U.S. government contractor Alan Gross.
"Cuba's continued incarceration of Alan Gross represents a significant impediment to a more constructive bilateral relationship and securing his immediate release remains a top priority of the United States," National Security Council spokesman Patrick Ventrell said in a statement.
"President Obama asked that President Mujica use any opportunity he might have to convey this same message to President Castro," Ventrell added.
Obama's request to Mujica was not initially disclosed by the administration following his visit.
Obama administration officials said the message to Castro is consistent with past White House calls for Gross' release.
Gross was convicted in 2011 for bringing satellite communications equipment into Cuba as part of his work as a subcontractor for the U.S. Agency for International Development.
U.S. officials have said Gross was simply trying to help Cubans bypass their government's stringent restrictions on Internet access.
CNN's Jim Acosta contributed to this report.