Jennings announced in April he had cancer and the anchor of ABC's "World News Tonight" died in New York Sunday at age 67.
"Laura and I were saddened to learn about the death of Peter Jennings," Bush's statement said. "Peter Jennings had a long and distinguished career as a news journalist. He covered many important events, events that helped define the world as we know it today. A lot of Americans relied upon Peter Jennings for their news."
"World News Tonight" senior broadcast producer Tom Nagorski praised Jennings' energy and tenacity.
Former CBS News Anchor Dan Rather told "The Early Show" Jennings was "a fierce competitor, but a principled one." NBC newsman Tom Brokaw told the "Today" show, his longtime friend and competitor was "born to be an anchor."
Jennings' ABC colleague Barbara Walters remembered Jennings as a stickler for details.
"If I knew the name of the person in the parade," she told CNN, "he knew the name of the horse."