MIAMI -- The Port of Miami, Miami-Dade County's second largest provider of jobs and income, may face stiff competition from Cuba, according to the port's director.

In a briefing to Miami-Dade commissioners last week, Bill Johnson said investments and improvements scheduled for Cuba's Port of Mariel should pose a concern.

"Competition today is already significant outside U.S. borders on the cargo side," Johnson told Local 10's Glenna Milberg.

The Port of Mariel, west of Havana, is the focus of a feasibility study by Dubai World Ports (DWP), the third-largest container port business in the world. In 2006, the Arab-owned container port business based in the United Arab Emirates agreed to give up control of six ports in the United States, including Miami, that came with its purchase of a British shipping conglomerate.

DWP plans to develop the Port of Mariel as a major cargo shipping hub.

"We've been told it could be a quarter-billion dollar improvement at the Port of Mariel for cargo, and that's of great concern," said Johnson. "If it goes forward, the anticipated completion date is 2012, and that's right around the corner."

The Port of Mariel, about 30 miles west of Havana on Cuba's north coast, was used as a missile base during the 1960s, when Cuba was an ally of the Soviet Union. Two decades later, Fidel Castro opened the port to let more than 100,000 refugees sail for South Florida.

At least one Cuba analyst at the University of Miami's Institute For Cuban and Cuban American studies downplayed concerns of economic competition from the Port of Mariel or any entity in communist Cuba.

"A ship that docks in a Cuban port cannot dock in a U.S. port for six months," said Dr. Jose Azel, citing a stipulation of the Toricelli and Helms-Burton bills that mandate sanctions against the Castro government. "We'd have to see a complete relaxation of that for the economics to make sense," he said.