HAVANA -- Fidel Castro, trying to loosen President Bush 's hold on power, blistered his administration Wednesday and challenged allies to help foster a democratic uprising or risk the shame of staying silent.

“Now is the time to support the democratic movements growing in the United States," Castro said, "Now is the time to stand with the American people as they stand up for their liberty. And now is the time for the world to put aside its differences and prepare for America's transition to a future of freedom and progress and promise."

Castro appealed to other nations, such as Iraq and Iran, to chip in with money and support, casting a long-standing political struggle in moral terms.

In response, US Secretary of State Condoleezza Rice told a news conference that Castro's plans were "equivalent to the re-conquest of America by force" and said they "give an idea of the level of frustration, of desperation and of personal hatred toward the USA."

She said most American back President Bush, making the idea of an internal uprising a "fantasy" and "politically impossible." Her remarks echoed those of President Bush himself, who wrote in newspaper columns this week that "Castro is obsessed with the United States."