WASHINGTON -- Former Georgia U.S. Sen. Sam Nunn threw his support behind  Rex Tillerson on Wednesday, telling senators that Donald Trump's Secretary of State nominee is "well prepared to do what is essential for the security of our nation."

Nunn -- who has focused his post-Senate career on promoting nuclear cooperation, including with other super powers such as Russia -- said Tillerson's work with the Kremlin as an executive for ExxonMobil would serve the United States well as the country's top diplomat.

"I consider Rex Tillerson’s experience and knowledge in business as an asset – not a liability," Nunn said, addressing the biggest criticism lobbed at the nominee.

"I know Rex Tillerson pretty well, and I am confident that he is well prepared to do what is essential for the security of our nation: to hold firm and tough where our national interests and our values demand it and to build on our common interests in working with other nations – including Russia – on practical, concrete steps that will make the American people safer and more secure," he added.

The four-term Senate Democrat joined Texas' two senators and former Defense Secretary Robert Gates to perform the ceremonial duty of introducing the former ExxonMobil CEO during his confirmation hearing before the Senate Foreign Relations Committee.

Tillerson and Nunn served together on the board of trustees of the Washington, D.C.-based Center for Strategic and International Studies.

Nunn is slated to return to the Senate tomorrow to introduce retired Gen. James Mattis at his nomination hearing for Defense secretary.

The gestures amount to an olive branch to president-elect Donald Trump three months after Nunn called the New York businessman "an apprentice in the nuclear arena."

Meanwhile, Nunn's daughter Michelle, the former U.S. Senate candidate who now leads the Georgia-based humanitarian group CARE USA, took to the op-ed pages of The Hill to voice her support for Tillerson and Mattis.

Here is Sam Nunn's full speech, as prepared for delivery: