From Vince Bugliosi's book.....
"British tabloid journalist Comer Clark...in an October 1967 edition of the National Enquirer...wrote that on July 15, 1967, he had an exclusive interview with [Fidel] Castro late one night in a Havana pizzeria. He quotes Castro as saying, "Lee Oswald came to the Cuban Embassy in Mexico City twice. The first time, I was told, he wanted to work for us. He was asked to explain, but he wouldn't. He wouldn't go into details. The second time he said something like: 'Someone ought to shoot that President Kennedy.' Then Oswald said--and this was exactly how it was reported to me--'Maybe I'll try to do it.' This was less than two months before the U.S. President was assassinated...Yes, I heard of Lee Harvey Oswald's plan to kill President Kennedy. It's possible I could have saved him. I might have been able to, but I didn't. I never believed the plan would be put into effect."
The HSCA learned that Clark, who died in 1972, "wrote extensively for the sensationalist press in England. His articles include such items as 'British Girls as Nazi Sex Slaves' [and] 'I Was Hitler's Secret Love'."
When the HSCA asked Castro on April 3, 1978, about Clark's allegation, he responded in a blizzard of denunciatory words. Among them: "This is absurd. I didn't say that. It has been invented from the beginning until the end. It's a lie from head to toe. If this man [Oswald] would have done something like that, it would have been our moral duty to inform the United States."
Denying that he had ever met Clark or been interviewed by him, [Castro] said, "How could [this man] interview me in a pizzeria? I never go to public restaurants...I would never have given a journalist an interview in a pizzeria...What is the job of that journalist? What is he engaged in? ... You should...find [out] who he is and why he wrote it." "
-- Vincent Bugliosi; Page 1285 of "Reclaiming History"