Morgan also penned the films "The Last King of Scotland" and "The Queen."
Keach is best known for his portrayal of detective Mike Hammer on television and for his roles in the films "The Heart Is a Lonely Hunter," "The New Centurions," "Escape from LA" and "American History X."
Stage and screen actor Alan Cox is to play renowned British talk-show host David Frost in the touring production of "Frost/Nixon."
Appearing alongside Keach and Cox are Meghan Andrews as Evonne Goolagong, Bob Ari as Bob Zelnick, Antony Hagopian as John Birt, Roxanna Hope as Caroline Cushing, Ted Koch as Jack Brennan, Stephen Rowe as Swifty Lazar, Brian Sgambati as Jim Reston and Noel Velez as Manobo Sanchez. Rounding out the ensemble are David Sitler, Peter Hilton and Tamara Lovatt-Smith.
Michael Grandage, who helmed the original London and Broadway productions, is directing the tour with associate director Seth Sklar-Heyn, representatives for the show said.
The tour officially opens in Des Moines, Iowa, at the Des Moines Civic Center Sept. 30 and is scheduled to travel to more than a dozen U.S. cities. It is to wrap up in Dallas May 3, 2009.