intelligence assessments, however, have reportedly warned that the Cuban political system may be considerably more resistant to such a transition. He called it "naive" for Cuba not to prepare, "looking at what's happening around the world. The reduction in fuel availability has compounded existing shortages and placed additional pressure on transportation, power generation and other essential services.United Nations officials warned earlier this year that U.S. sanctions had already contributed to severe shortages of essential medical supplies in Cuba. The latest fuel blockade was also reported to have doubled infant mortality on the island, adding to concerns about the humanitarian consequences of the economic restrictions.Several countries have responded by increasing assistance to Havana.while Moscow has pledged continued political, diplomatic and material support. At the same time, U.S. intelligence assessments cited by the Times indicate that finding a Cuban official willing and capable of taking power — particularly under circumstances involving direct American intervention — may prove substantially more difficult than the administration's experience in Venezuela.