President-elect Donald Trump has nominated Rex Tillerson to be the next U.S. secretary of state, saying in a Dec. 13 tweet that the chairman and CEO of oil and gas giant Exxon Mobil Corp. is "one of the truly great business leaders of the world."

Trump's transition team later issued a news release to announce the nomination, calling Tillerson one of the world's most accomplished "international dealmakers" and pointing to a career spent protecting jobs.

"Rex knows how to manage a global enterprise, which is crucial to running a successful State Department, and his relationships with leaders all over the world are second to none. I can think of no one more prepared, and no one more dedicated, to serve as Secretary of State at this critical time in our history," Trump said in the news release.

Tillerson said in a statement that he shares Trump's vision for "restoring the credibility of the United States’ foreign relations and advancing our country’s national security." He added that the country "must focus on strengthening our alliances, pursuing shared national interests and enhancing the strength, security and sovereignty of the United States."

Other candidates who had reportedly been in the running for the post were Mitt Romney, David Petraeus and Sen. Bob Corker.

Romney tweeted late Dec. 12: "It was an honor to have been considered for Secretary of State of our great country."