HAVANA - Ailing Cuban leader Fidel Castro said on Tuesday that he will not return to lead the country as president, retiring as head of state 49 years after he seized power in an armed revolution.

Castro, 81, said in a statement to the country that he would not seek a new presidential term when the National Assembly meets on February 24.

"To my dear compatriots, who gave me the immense honor in recent days of electing me a member of parliament ... I communicate to you that I will not aspire to or accept -- I repeat not aspire to or accept -- the positions of President of Council of State and Commander in Chief," Castro said in the statement published on the Web site of the Communist Party's Granma newspaper.

The National Assembly or legislature is expected to nominate his brother and designated successor Raul Castro as president in place of Castro, who has not appeared in public for almost 19 months after being stricken by an undisclosed illness.

His retirement drew the curtain on a political career that spanned the Cold War and survived U.S. enmity, CIA assassination attempts and the demise of Soviet Communism.

A charismatic leader famous for his long speeches delivered in his green military fatigues, Castro is admired in the Third World for standing up to the United States but considered by his opponents a tyrant who suppressed freedom.