Most of Cuba's petroleum demand is met by Venezuela and there is no commercial production from deep offshore reserves, the U.S. Geological Survey said.

USGS said it produced a briefing on Cuba's extractive industries in response to the re-establishment of diplomatic ties with the United States. Ties between both countries were severed in 1961.

Prior to the trade embargo enacted in 1962, U.S. companies held interests in several petroleum refineries in Cuba. Now, USGS said Venezuela dominates the sector by meeting more than 60 percent of the country's petroleum demand. The second largest refinery in Cuba processes only Venezuelan crude oil.

Most of the Cuban petroleum production comes from coastal reserve areas east of Havana.

"As of 2015, deepwater drilling by such foreign companies as Repsol of Spain and Zarubezhneft of Russia has resulted in no discovery of commercial quantities of oil or gas," the USGS report read.

The report follows a bill introduced last week by two Florida congressmen that would force companies to pay for oil cleanup on U.S. soil. Rep. Carlos Curbelo, R-Fla., and his Democratic counterpart, Patrick Murphy, said they were concerned about Havana's oil spill response plans now that Cuba was opening its doors.

A delegation from the U.S. National Oil Spill Commission visited Cuba in 2011 to examine Havana's oil plans. Cuba the same year announced plans to ease the dependency on Venezuela by developing its offshore reserves.

USGS estimated there were about 4.6 billion barrels of crude oil and 9.8 trillion cubic feet of natural gas in the form of undiscovered, technically recoverable, reserves in Cuba. About three quarters of that is said to be located within 50 miles from shore.