PEOPLE has learned the former World News anchor has snagged the much-anticipated first sit-down with Jenner, who's already prepping a reality show about his transition.
It's unclear when the interview will take place or air, but it's likely to serve as a walk-up to Jenner's docuseries that will run on E! this year.
It's been widely reported the docuseries won't air until Keeping Up with the Kardashians finishes its season – and Jenner gives it a thumbs-up.
"It will air when he is ready to be open about his transition," a source told PEOPLE. "But he's acting more and more confident and seems very happy."
Sawyer stepped down from her five-year role as World News anchor on Aug. 27, but she told viewers that she wasn't "going far."
She recently returned to the nightly news show to promote her story on sex trafficking that aired on Nightline and Good Morning America.
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