Fidel Castro had prior knowledge that US President John F Kennedy was about to be killed, according to a new book by a retired CIA analyst. Rumours about the Cuban leader's involvement in a plot to murder his fierce adversary have swirled for almost half a century since communist sympathiser Lee Harvey Oswald shot the US president during a trip to Dallas in November 1963. Now author Brian Latell, who studied Cuban affairs as a CIA analyst in the 1960s and later became the agency's chief intelligence officer for Latin America, says he is certain that Castro at least knew the attack was going to happen. On the morning of November 22, 1963, the day Kennedy was killed, Castro ordered a senior intelligence officer in Havana to stop listening for non-specific CIA radio communications and concentrate instead on "any little detail, any small detail from Texas", Latell claims in his new book 'Castro's Secrets - the CIA and Cuba's Intelligence Machine', set for release next month. Four hours later, the airwaves came alive with news that Kennedy was dead. Latell also claims that Castro was aware that Oswald, who had been denied a visa to visit Cuba at the country's embassy in Mexico City, told staff there that he was going to murder Kennedy to prove his allegiance to the communist cause. "Fidel knew of Oswald's intentions and did nothing to deter the act," the Daily Mail quoted Latell as saying in his book. In an interview published in The Miami Herald, the author, now a respected senior lecturer on Cuba at the University of Miami, says he discovered the information in interviews with former Cuban intelligence officers, backed up by declassified US government documents. "I don't say Fidel Castro ordered the assassination, I don't say Oswald was under his control. He might have been, but I don't argue that, because I was unable to find any evidence for that," he said. Subsequent investigations by the US security agencies, and the official Warren Commission inquiry into Kennedy's assassination, looked at Castro's possible involvement but concluded that Oswald was a lone gunman acting independently.