Acting Cuban President Raul Castro appeared in public for the first time on Sunday (August 13) to officially greet Venezuela's President Hugo Chavez who arrived to the island to celebrate Fidel Castro's 80th birthday while he recovers from having surgery for gastrointestinal bleeding. The Cuban leader relinquished power to his younger brother Raul on July 31 due to stomach surgery. Cuban television showed Chavez embracing Raul who was flanked by other Cuban officials including Vice President Carlos Lage. A Cuban newspaper on Sunday published the first photographs of Fidel Castro since his surgery, and the Cuban leader, shown wearing a sweat suit and sitting in a chair, said he had stabilized "considerably" but was not out of the woods. He sent a message to Cubans on his 80th birthday that was published by youth daily Juventud Rebelde with four waist-up photographs of him speaking on the telephone, apparently sitting in a chair. One photograph showed Castro holding a copy of the special supplement that the Communist Party newspaper Granma published on Saturday (August 12) for his birthday, an apparent move to show the pictures were current. Authorities called for voluntary work in the fields and factories to honour the Cuban leader. The official media called on the population to "a huge productive day on Sunday as a dignified present to Fidel and the motherland." Sugar Minister General Ulises Rosales del Toro, led 500 workers doing an extra stint in a cane field outside Havana in homage to Fidel. "We celebrate the Comandante's recuperation with more production, with more discipline. Long live Fidel, long live Raul, country or death," he said. "This is the best way for Fidel to recuperate and to honour the 80th anniversary of his birth," said volunteer Enrique Fernandez. Scores of residents in the capital were also out and about carrying out voluntary work. Cubans were also being urged to donate blood and clean up their neighbourhoods. "The best kind of support we can give him is by volunteering to work and to wish him to get well," Havana resident Juan Contreras said. Major celebrations of his birthday were postponed until December 2, the 50th anniversary of his landing in eastern Cuba with a boatload of rebels to launch the guerrilla war that later brought him to power. Meanwhile, in a school in Havana, hundreds of children gathered to decorate a cake in honour of Castro's birthday. "We feel proud that with our innocence and with our thoughts and ideas, with our flowers and our illusions, we offer happiness (to Fidel Castro on his birthday)," one student said. Details of Castro's health are considered a state secret, so there has been little information about his condition or even confirmation he was alive. It is not known whether Castro will be able to resume his government duties. Cuban officials have said the workaholic Castro will have to lessen his workload if he is to recover. Castro is the last of the key Cold War-era figures on the world stage and has survived through the administrations of 10 U.S. presidents, despite their efforts to oust him, and the collapse of Cuba's previous benefactor, the Soviet Union.