In a rare public appearance, former Cuban leader Fidel Castro attends an opening ceremony of a school named after the Cuban Revolution heroine Vilma Espin on April 9, 2013 in the capital Havana. Fidel has rarely been seen in public since his retirement in 2006, the official Granma daily reported. [Photo/Xinhua]

HAVANA - Former Cuban leader Fidel Castro opened a school in Havana in a rare public appearance since his retirement in 2006, the official Granma daily reported Thursday.

Castro, 86, spoke for two hours with the students and teachers at the school about climate change, weapons of mass destruction, economic crisis, high fuel prices and many other issues, according to Granma.

"In these circumstances, life on earth is difficult," he was quoted as saying.

It was Castro's idea to build the 140-student facility in a Havana district, said Granma.

Castro was last seen in public on February 24 at a parliament session that named the new head of government.

Castro handed over power to his brother Raul Castro in 2006 for health reasons.

A Venezuelan journalist who said he interviewed Fidel Castro for four hours on March 31, described the former Cuban leader as "vigorous, healthy, lucid, intelligent, throwing out endless figures and measures, names and situations."

Former Cuban leader Fidel Castro attends an opening ceremony of a school named after the Cuban Revolution heroine Vilma Espin on April 9, 2013 in Havana, Cuba. It was a rare public appearance since his retirement in 2006, the official Granma daily reported.[Photo/Xinhua]