Former US secretary of state Warren Christopher died late Friday at the age of 85, the daily New York Times reported on Saturday.
Christopher had been suffering from kidney and bladder cancer, dpa reported.
Secretary of State Hillary Rodham Clinton mourned Christopher's passing.
"I was deeply saddened by the passing of my friend and predecessor Warren Christopher. The longer I spend in this job, the deeper my appreciation grows for the giants who came before," she said.
Christopher served as secretary of state under president Bill Clinton 1993-97 and was heavily involved in efforts to end fighting in the former Yugoslavia during the 1990s and expand NATO.
"America is safer and the world is more peaceful because of his service," said Clinton.
Christopher is survived by his wife and four children.