Stalin apparently learned of Wayne's popularity from the Russian filmmaker Sergei Gerasimov, who attended a peace conference in New York in 1949. Michael Munn, a film historian and author of John Wayne - The Man Behind The Myth, said Gerasimov told Stalin of Wayne's fervent anti-communist beliefs.

"Stalin decided that he would have him killed," said Mr Munn, who says he was told of the plot by Orson Welles at a dinner in 1983. Welles had said that the KGB was given the task of assassinating Wayne.

"Mr Welles was a great storyteller," said Mr Munn, "but he had no particular admiration for John Wayne." He said that Welles had offered the story without prompting, and that his sources were excellent.

A prominent Russian filmmaker, Alexei Kapler (who was imprisoned for an affair with Stalin's 16-year-old daughter, Svetlana), had told another Russian filmmaker, Sergei Bondachuk, about the order. Bondachuk was sceptical at first, but after Gerasimov confirmed the story, Bondachuk told Welles.

Mr Munn said Wayne had also told him that his friend, the stuntman Yakima Canutt, had "saved his life once". Mr Munn later asked Mr Canutt what he had meant by this comment. The incident is thought to have taken place in the early 50s.

"Yakima told me that the FBI had discovered there were agents sent to Hollywood to kill John Wayne," said Mr Munn. "He said the FBI had come to tell John about the plot. John told the FBI to let the men show up and he would deal with them."

Wayne then apparently hatched a plot with his scriptwriter at the time, Jimmy Grant, to abduct the assassins, drive to a beach and stage a mock execution to frighten them. Mr Munn said he did not know what transpired, but heard the two men stayed in the US to work for the FBI.

"Afterwards though, John shunned FBI protection and did not want his family to know. He moved into a house with a big wall around it."

Wayne then relied upon a group of loyal stuntmen who infiltrated communist cells in America and learned of plots to kill him.

"He then gathered all the stuntmen, went to the communist meetings, and had a huge fight," Mr Munn said. This was when Wayne believes Mr Canutt saved his life.

A further attempt to kill Wayne was made in Mexico on the set of the film Hondo (which was released in 1953), led by a communist cell, according to Mr Munn.

The book claims that Stalin's order was cancelled by his successor Nikita Krushchev after the dictator's death in 1953. The book says Krushchev told Wayne in a private meeting in 1958: "That was a decision of Stalin during his last five mad years. When Stalin died, I rescinded that order."

Wayne also told Mr Munn about an attempt to kill him by an enemy sniper while he was visiting the troops in Vietnam in 1966. "One of the snipers was captured," said Mr Munn, "and said there was a price on John's head, put there by [China's communist leader] Mao Tse Tung."

Mr Munn said he had gathered the anecdotes over decades of work in the film industry. "I am quite convinced that it was not propagated by John or his inner circle," he added.