Branstad, the longest-serving governor in U.S. history, has accepted the offer, said Miller, who noted that Trump announced the pick in remarks in New York City this morning at a fundraiser closed to the press. A formal statement announcing the pick is expected later today.
The governor has a decades-long relationship with China's President Xi Jinping. The two first met in 1985 when Xi was part of a Chinese delegation visiting Iowa. Shortly after Trump's election last month, Branstad visited China on a trade mission.
Branstad, 70, who campaigned with Trump in Iowa, met with him at Trump Tower in New York on Tuesday. Branstad's son Eric Branstad served as Trump's Iowa director.
The ambassador position will require Senate confirmation.
Terry Branstad began his second stint as governor in 2011, first serving from 1983 to 1999.