US President George W Bush says he is hoping for a democratic transition in Cuba, after Fidel Castro resigned as president.
"I believe that the change from Fidel Castro ought to begin a period of a democratic transition," Bush said at a news conference in Rwanda during a five-country African trip.
The ailing Castro, 81, announced he was retiring after nearly a half-century in power, positioning his 76-year-old brother, Raul, for permanent succession to the presidency.
Bush urged the international community to help Cuba shift toward democracy, and said the United States would Cuba realise the "blessings of liberty".
"The international community should work with the Cuban people to begin to build institutions that are necessary for democracy," Bush said.
Castro announced he will not return to lead the country as president or commander-in-chief, retiring as head of state 49 years after he seized power in an armed revolution.
Bush said the first step should be to free political prisoners, and the international community should work with Cubans to start building institutions necessary for democracy.
"Eventually this transition ought to lead to free and fair elections, and I mean free and I mean fair," Bush said.
"Not these kind of staged elections that the Castro brothers try to foist off as being true democracy," he said.
"And we're going to help. The United States will help the people of Cuba realise the blessings of liberty," Bush said.
Washington's relations with Cuba have been hostile since soon after Castro came to power in 1959 and began steering the island on a course that aligned it with the Soviet Union during the Cold War.
The United States has maintained an economic embargo on Cuba for more than four decades to try to isolate Castro.
The Bush administration greeted Castro's illness and his provisional hand-over of power in the summer of 2006 coolly, since it did not expect much change to the one-party system under his brother, Raul Castro.
Fidel Castro had temporarily ceded his powers to his brother on July 31, 2006, when he announced that he had undergone intestinal surgery.