The book, Taking Charge: The Johnson White House Tapes 1963-64, from Simon and Schuster, transcribes tapes of private meetings secretly recorded by LBJ after he was sworn in to replace Kennedy. In the tapes, Johnson reacts to FBI surveillance which showed that Kennedy's killer, Lee Harvey Oswald, had visited the Cuban and Soviet embassies in Mexico City two months before the November 1963 assassination.
Johnson and an old friend, Senator Richard Russell of Georgia, both say they do not believe the Warren Commission report that Oswald acted alone. Russell, a commission member, said he had been forced to sign the report against his will, according to excerpts from the book published in Newsweek.
More than three years later, LBJ is told of past attempts by the Kennedy administration to assassinate Castro. "It's just incredible," Johnson tells his Attorney-General, Ramsey Clark. "They have a man that was instructed by the CIA and the Attorney-General [Robert Kennedy] to assassinate Castro after the Bay of Pigs. They had these pills and they were supposed to take them [if Castro] caught them. And they didn't get to take their pills. So he tortured them and they told him all about it. So he called Oswald and a group in and told them... 'Go get the job done.'"
The Cuban leader has always scoffed at the rumours.