Fifty years after Fidel Castro's guerrillas claimed control of Cuba, the country's communist leadership will celebrate Thursday's landmark anniversary amid a deepening economic crisis and speculation about the frail health of the father of that revolution.

Castro's younger brother Raul, 77, who replaced the veteran dictator as president in February, will lead the main celebrations in the eastern city of Santiago, addressing a crowd from the same balcony where Fidel proclaimed victory on Jan 1, 1959.

Concerts are planned throughout the country, with the major one in Havana where popular Cuban band Los Van Van will play at the so-called Anti-Imperialist Tribunal in front of the US Interests Section, America's de facto embassy.