In his new book, " Richard Burton: Prince of Players," writer Michael Munn alleges the noted ladies man cheated on his first wife, Sybil Williams, with the "Some Like It Hot" actress, the Daily Mail said Saturday.
The late actor's former publicist also alleges in his book that Burton had an extramarital affair with his "The Rains of Ranchipur" co-star, actress Lana Turner.
Yet it is Munn's allegations of Burton's infidelity with Monroe that will likely garner the most attention as they mark the first time the "Becket" star was linked to the famed Hollywood actress.
The British newspaper said that in "Prince," Munn alleges the couple's illicit affair lasted throughout the 1950s and the early portion of the 1960s, when Burton and Williams officially split.
Munn's book is due out in stores next month.