WASHINGTON — President Barack Obama plans to nominate Gary Locke, the commerce secretary and one of the highest-ranking Chinese-Americans in the administration, as the next U.S. ambassador to China, administration officials said Monday. Locke, 61, would succeed Jon M. Huntsman Jr., who is stepping down next month to explore a bid for the Republican nomination for president.

Locke, a former governor of Washington, was both the first Chinese-American commerce secretary and the first Chinese-American governor, serving for two terms, from 1996 to 2005. He was born in Seattle, the son of immigrants from Hong Kong, and traces his Chinese ancestry to southern Guangdong province.

Before going to Washington, Locke built a reputation as an expert on trade relations with China. While governor, he made several trade trips to China on behalf of Washington, which is often referred to as the nation’s most trade-dependent state, as the manufacturing base of Boeing, among other exporters.