Let's get one thing straight. Natural resources by natural right belong to the people. Not to just a few rich people (as in Capitalism), nor to the State (as in Socialist Cuba). They belong to the people, i.e. every individual man, woman and child. God did not create them just to be exploited by the rich, nor by the State. The State is a man-made construct, which has the right and duties the people decide to concede it. Sovereignty remains with the people.
When ever were the people asked to pass the property of natural resources to the State? Never. The State expropriated them to be exploited on behalf of and for the benefit of the people. But in reality this just means that the people have lost their natural birthright. In a Solidarist society this birthright will be restored.
Give the Cuban people back what is theirs
The grave error Fidel Castro made was his belief that if the State would expropriate all the means of production and natural resources, this would empower the people. It does not as he can also realize by now. The State is an abstract entity with a natural tendency to become tyrannical. It should be entrusted with as few tasks as possible, i.e. only with those that are really best done collectively. Whatever can be done by the people should not be entrusted to the State. And unless the people have a direct say in this construct called the State, they lose all power. This is crystal clear in Cuba.
Solidarism will give the Cuban people back what was theirs all along, i.e. both the means of production and Cuba's natural resources. In a Solidarist society every Cuban citizen would receive free of cots one non-transferable share (with full voting right) in the Cuban Bank of Natural Resources. This Bank would commercially exploit all Cuba's natural resources, such as nickel, copper, marble, cement, wood, beaches, petroleum etc.. Commercial exploitation means at the maximum profit possible. Each year all profit - after deduction of reasonable taxes to a small State - would be distributed as dividend to the Cuban people. If the management of this bank were not doing a good job, the people would have the right to dismiss them and nominate new managers. This is one meaning of the Solidarist concept of "Economic Democracy". This is real power to the people. Not to the State, but to the people. Raoul Castro, please consider this proposal carefully.