U.S. Secretary of State John Kerry on Thursday called a Cuban law that bars anyone born on the island from returning by ship is discriminatory and said it should be eliminated.
Kerry said the policy should be eliminated if Cuba's communist government is dedicated to having a full and normal relationship with the rest of the world.
"The United States government will never support, never condone discrimination, and the Cuban government should not have the right to enforce on us a policy of discrimination against people who have a right to travel," Kerry said in an interview with CNN en Español and the Miami Herald.
"We should not be in a situation where the Cuban government is forcing its discrimination policy on us," he added. "If they want a full relationship and a normal relationship they have to live by international law."
Kerry stopped short of saying Carnival should cancel its planned route to Cuba, but said "Carnival needs to not discriminate."
The United States also has a complicated set of entry and immigration standards that aren't the same for people of every nationality.
Carnival Corp. has denied ticket sales to Cuban Americans because of the law, saying it has to comply with the visa, entry and exit policies of every country its ships visit. But the company said it has lodged a request with the Cuban government to change the ship policy.
Two Cuban-Americans are suing Carnival Corp., claiming their civil rights were violated by the policy, which only applies to travel by ship, not other modes of transportation to Cuba.
Kerry met in Miami with members of the Cuban-American business community. He also spoke to honor students at a Miami Dade College event.
The United States and Cuba began normalizing diplomatic relations in late 2014 after more than a half century of estrangement. Since then, both countries have reopened their respective embassies in Washington and Havana, and last month President Barack Obama became the first sitting U.S. president to visit the island nation in nearly 70 years.
In advance of Obama's historic trip to Havana, the government made it easier for Americans to travel to Cuba by allowing travelers to take "people-to-people" trips to the country on their own instead of with expensive tour groups. The rule change turned a ban on U.S. tourism to Cuba into an unenforceable honor system.
Obama previously opened the door to restoring commercial air traffic between the U.S. and Cuba and the two countries have also agreed to a pilot program restarting direct mail service; signed two deals on environmental protection and launched talks on issues from human rights to compensation for U.S. properties confiscated by Cuba's revolution.
While the thawing of relations has been touted by the Obama administration, the effort has not been universally lauded. Republican lawmakers have balked at the idea of restoring diplomatic ties and the move has become an issue in the 2016 presidential campaign.
Texas Sen. Ted Cruz, whose father was born in Cuba, has objected to the renewed ties and said Obama shouldn't have visited the island while the Castro family remains in power.
The decades-old trade embargo also still remains in place and can't be abolished without approval from Congress.
Kerry said Thursday that Cuba needs to continue to address human rights reforms, among other changes, before the embargo is likely to be lifted.
Based on reporting by The Associated Press.