Cuba's parliament opened its year-end session Friday with the chair normally occupied by Fidel Castro empty, in the first meeting of the National Assembly of Popular Power since the 80-year-old leader fell ill.

The session traditionally features dry speeches peppered with economic figures. But Cubans were riveted to Friday's meeting because of the mystery surrounding Castro's health after his July 31 intestinal surgery.

As the session began, lawmakers sang the national anthem and observed a minute of silence for a parliament member who had died.

Raul Castro, who temporarily took power from his elder brother after the surgery, sat in his customary seat just to the left of the chair normally used by Fidel Castro. National Assembly President Ricardo Alarcon, as usual, presided over the session.

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Fidel Castro typically attends the meetings, asking questions of speakers giving their annual economic reports and sometimes giving speeches of his own.

Castro loyalists were deeply disappointed early this month when the bearded guerrilla leader did not show up for a major military parade marking the 50th anniversary of Cuba's Revolutionary Armed Forces and belated celebrations of his Aug. 13 birthday.

Castro has not been seen in public since July 26 — five days before he stepped aside — and his medical condition has since been kept a state secret. He has been seen occasionally in official photographs and videos since, and appeared thin and frail in the last one released in late October.

Cuban officials have insisted that Castro will recover and return to public life, but many acknowledge privately that it seems increasingly unlikely he will resume his once powerful role.

They have repeatedly denied that Castro suffers from cancer or some other terminal ailment, as U.S. intelligence officials and others have speculated.

Some U.S. doctors have said that Castro might have diverticular disease, which can cause bleeding in the lower intestine, especially in people over 60. In severe cases, emergency surgery may be required.

Raul Castro, the 75-year-old defense minister, has been signaling a more collaborative leadership style since assuming provisional power, delegating more responsibilities and calling for more public debate.

In Friday's session, Raul Castro was surrounded by other members of the leadership, including vice presidents Carlos Lage and Esteban Lazo and Foreign Minister Felipe Perez Roque.

The nearly 500 members of Cuba's National Assembly are directly elected every five years in district balloting across the island. Although Communist Party membership is not required to run, no other political parties are recognized in Cuba, and deputies often run unopposed.

Also every five years, the National Assembly elects Cuba's governing body, the Council of State, including its president.

Castro was elected by National Assembly deputies to his sixth presidential term in March 2003. At the same time, they re-elected Raul Castro as the council's first vice president, ratifying his role as his brother's constitutionally designated successor.

Following that vote, the elder Castro made what was then a rare reference to his mortality.

"I promise that I will be with you, if you so wish, for as long as I feel that I can be useful — and if it is not decided by nature before," he said. "Not a minute less and not a second more."