Hoping to scoop the world on one of America's supreme historical puzzles, Germany's leading television broadcaster will claim in a documentary film tonight that it was the Cuban secret service that organised the assassination of President John F. Kennedy.

The 90-minute film, titled Rendezvous with Death, features an interview with Oscar Marino, a former agent of the Cuban G2 secret service, who says he knew before the assassination in November 1963 that Lee Harvey Oswald - Kennedy's killer - had been picked by his colleagues to do the job.