It was not immediately clear where the cancer had spread. Carter—who served as 39th U.S. president from 1977 to 1981—said he will release more details on his situation, "possibly by next week."

"Recent liver surgery revealed that I have cancer that now is in other parts of my body," Carter said in a statement. "I will be rearranging my schedule as necessary so I can undergo treatment by physicians at Emory Healthcare."

Jimmy Carter revealed Wednesday he has cancer, saying it was discovered after an operation on the 90-year-old former president's liver earlier this month.

The Aug. 3 operation was to remove a "small mass" from his liver, according to The Associated Press. After the procedure, Carter's prognosis for a full recovery was initially thought to be "excellent," a spokeswoman for his nonprofit The Carter Center told the AP.

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President Barack Obama sent his best wishes for a fast, full recovery Wednesday afternoon. "Jimmy, you're as resilient as they come, and along with the rest of America, we are rooting for you," he said, in a statement.



Carter has stayed active with his nonprofit, which was founded in 1982 and focuses on health care and human rights, among other initiatives. Health issues have affected some of his work this year, like a May trip to Guyana that was cut short by a bad cold.

He recently completed a tour for a new book, "A Full Life: Reflections at Ninety."

Carter won the Nobel Peace Prize in 2002 for what the prize committee called "decades of untiring effort to find peaceful solutions to international conflicts." The native of Plains, Georgia, was the state's governor before his election to the White House.

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—The Associated Press contributed to this report