U.S. President-elect Donald Trump on Thursday made the first appointment of his new administration — naming a chief of staff — with other key jobs set to be filled in the "days and weeks ahead," according to his team.

"There are some people that will be returning (from Trump's first term)," senior Trump aide Jason Miller told Fox Business on Wednesday. "And they'll be some new people joining the mix."

Linda McMahon, a former CEO of World Wrestling Entertainment, and Howard Lutnick, the founder of the brokerage firm Cantor Fitzgerald, are leading the transition process.