HAVANA - Former Cuban leader Fidel Castro suggested Thursday his health is failing, saying by the end of U.S. President Barack Obama's first term he doesn't expect to be following current events.

In an online column called "Reflections of Comrade Fidel," the longtime Cuban leader appeared to be pondering his own mortality, saying Cuban officials "shouldn't feel bound by my occasional Reflections, my state of health or my death."

"I have had the rare privilege of observing events over such a long time. I receive information and meditate calmly on those events," he wrote.

"I expect I won't enjoy that privilege in four years, when Obama's first presidential term has ended."

He didn't elaborate.

The bulk of the column was devoted to praising Obama, in part for his decision to close the prison camp at Guantanamo Bay. Obama is the 11th U.S. president Castro, 82, has seen in nearly a half-century of antagonistic relations between the superpower and the communist country.

"The intelligent and noble face of the first black president of the United States...had transformed itself under the inspiration of Abraham Lincoln and Martin Luther King into a living symbol of the American dream," Castro wrote.

However, he suggested Obama would soon fall victim to the U.S. system.

"What will he do soon, when the immense power that he has taken in his hands is absolutely useless to overcome the unsolvable, antagonistic contradictions of the (capitalist) system?"

The column, released Thursday evening, was the second in as many days. Before that, Castro hadn't been heard from in more than a month, fuelling rumours he was gravely ill.

Castro hasn't been seen in public since July 2006, when he had emergency surgery. He turned over the presidency to his younger brother Raul in February after nearly 50 years as Cuba's leader.