The United States DOES NOT rule Cuba. Cubans rule Cuba.
Barack Obama does not rule Cuba and Donald Trump does not rule Cuba. They may have 'opinions,' but they are not laws in Cuba.
Only the laws approved by Cuban Parliament (which is called La Asamblea Nacional del Poder Popular) are legal and obeyed in Cuba.
U.S. laws do not have extraterritoriality, which is prohibited to all the members of the United Nations.
Cuba, and its President of the Council of State, do not accept dictates from the U.S. government.