Cuba's ailing leader, Fidel Castro, has resigned as president and commander-in-chief, more than 49 years after seizing power in an armed revolution.
The 81-year-old leader announced his decision in a letter on Tuesday in the Communist party newspaper, Granma. Mr. Castro said it would be a betrayal of his conscience to accept more responsibility than he is physically able to fulfill.
Mr. Castro said his decision is not a farewell to the Cuban people, and that he will continue to write about his thoughts.
U.S. President George W. Bush reacted to the news while on a trip to Africa, saying he hopes Mr. Castro's resignation will mean the beginning of a democratic transition in communist-led Cuba. He said political prisoners should be freed and Cuba should have free and fair elections.
Mr. Castro did not say who he thought should be his successor. Defense Minister Raul Castro has been serving as interim president since his older brother underwent intestinal surgery in July 2006.
Tuesday's announcement comes five days before Cuban officials are to select the island's top ruling body, the Council of State, and its president. Fidel Castro is expected to remain on the 31-member ruling council but says he will not compete for the top post.
Mr. Castro is the longest-serving leader in the Americas. He has not appeared in public since his surgery, but letters attributed to him have appeared in the Cuban media and he has been seen on state television meeting with international officials. Details of his health are considered a state secret.