Former Cuban leader Fidel Castro has cast doubt on whether a new president in the United States will change the country's policies.

In an essay posted online Friday, the ailing former leader did not mention President-elect Barack Obama by name. But in an apparent reference to the Democrat, he said it is "naive" to think the "good intentions" of one "smart person" could change what he called "the result of centuries of selfishness."

Mr. Castro said contempt for incumbent President George Bush has caused "illusions" in some people that the United States will be "more tolerant" and "less hostile" when a new leader takes office.

Before the election, Mr. Castro praised Mr. Obama in the state-run "Granma" newspaper, calling him more "intelligent" and "level-headed" than his Republican rival, John McCain.

Since Mr. Obama's victory, the 82-year-old former leader and his younger brother - Cuba's current president, Raul Castro - have not directly commented on the new president-elect.

Fidel Castro ruled Cuba for almost half-a-century. He formally ceded power to his brother in February after giving up the post on a provisional basis following intestinal surgery in 2006.

Mr. Castro has not been seen in public since the surgery, but he regularly releases essays on international issues.

Some information for this report provided by AP and Reuters.