Historic Cuban leader Fidel Castro accused British Prime Minister Gordon Brown of treating peers, including US President Barack Obama, "with prejudice" during the recent Group of 20 summit in London, according to dpa. In an article that the Cuban Communist Party daily Granma published Wednesday under his name, Castro further accused host Brown of having behaved in a "visibly derogatory" fashion toward the representatives of the Third World. "According to sources totally worthy of credit, the prime minister of Great Britain behaved in a visibly derogatory way with Third World participants. He treated Obama himself with prejudice due to his nature as a black man," Castro said. This was his fourth article in less than 24 hours. In an earlier piece, the former Cuban president, 82, said late Tuesday that his country would not return to the Organization of American States (OAS), from which the Caribbean island was suspended in 1962 under US pressure. "I was cautious with OAS, I did not say a single word that might be interpreted as an offense against the ancient institution, although everybody knows how much repugnance it inspires in us," he said. Castro was referring to an interview of OAS Secretary General Jose Miguel Insulza by the Brazilian daily O Globo. "Cuba has to clearly express its commitment to democracy if it wants to join OAS, in line with demands from a growing group of Latin American governments," Insulza said. Castro reacted with disdain. His comments came ahead of the Summit of the Americas which is set to gather 34 countries in the hemisphere - all except Cuba - from Friday in Trinidad and Tobago.