What David Letterman Said To Oprah About Retiring A Year Before His Big Announcement (VIDEO)

David Letterman, the longest-running late-night host in U.S. television history, has announced his retirement from CBS. Come 2015, Letterman will step down from his role as host of "Late Show with David Letterman" after 31 years in the late-night spotlight.

On last night's episode of his show, Letterman expressed his gratitude for all the support he's received over the years. "I just want to reiterate my thanks for the support from the network, all of the people who have worked here, all of the people in the theater, all the people on the staff, everybody at home," he said. "Thank you very much."

This isn't the first time Letterman has spoken publicly about his eventual retirement. A year ago, he sat down with Oprah Winfrey for an episode of "Oprah's Next Chapter" and spoke candidly about the right time to leave his late-night job and the understanding he had with his CBS CEO Leslie Moonves.

"[Moonves] and I have an agreement," Letterman said. "When he wants me to go, all he's got to do is call and say, 'You know, Dave, it's time to go.' And I'll go."

Even then, Letterman seemed comfortable with the idea of retirement. "I'll miss doing what I'm doing, but I won't feel like I have left anything on the table," he told Oprah.

The comedian also explained his willingness to defer to Moonves to make the call. "When it's time to go, somebody else tell me. Because I don't know when it's time to go. I feel like it's time to go now!" he joked.

In last night's announcement, Letterman mentioned that agreement he had discussed with Oprah a year prior."[Moonves] and I have had this conversation in the past and we agreed that we would work together on this circumstance and the timing of this circumstance," Letterman explained. "I phoned him just before the program and I said, 'Leslie, it's been great, you've been great, the network has been great, but I'm retiring."

In a statement released by CBS, Moonves praised Letterman both professionally and personally. "There is only one David Letterman. His greatness will always be remembered here, and he will certainly sit among the pantheon of this business," Moonves said. "On a personal note, it's been a privilege to get to know Dave and to enjoy a terrific relationship. It's going to be tough to say goodbye. Fortunately, we won't have to do that for another year or so. Until then, we look forward to celebrating Dave's remarkable show and incredible talents."

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