WASHINGTON -- Senate Foreign Relations Committee Chairman Bob Corker (R-Tenn.) announced today that he won't seek a third term next year, and hinted at critical things he may be faced with as a senator before his term expires.

"After much thought, consideration and family discussion over the past year, Elizabeth and I have decided that I will leave the United States Senate when my term expires at the end of 2018," Corker said in a statement. "When I ran for the Senate in 2006, I told people that I couldn’t imagine serving for more than two terms. Understandably, as we have gained influence, that decision has become more difficult."

"But I have always been drawn to the citizen legislator model, and while I realize it is not for everyone, I believe with the kind of service I provide, it is the right one for me," he added.

"I also believe the most important public service I have to offer our country could well occur over the next 15 months, and I want to be able to do that as thoughtfully and independently as I did the first 10 years and nine months of my Senate career."

Corker, a former mayor of Chattanooga, called serving in the Senate "the greatest privilege of my life."

"And as I spent the month of August traveling across our great state, I was reminded that we live in a unique place full of people who care deeply about the direction of our country," he added. "I am grateful to the people of Tennessee for the opportunity to serve my state and country. I have been fortunate to do so with an extraordinary staff, and I want to thank them for their incredible dedication. I know that we will continue to have an impact for the remainder of our term, and I look forward to finding other ways to make a difference in the future."

Corker campaigned with President Trump last year; this August, the senator told a Rotary Club in his home state that Trump "has not yet been able to demonstrate the stability, nor some of the competence, that he needs to demonstrate in order for him to be successful," and predicted "great peril" for the country unless the president "understands what has made this nation great and what it is today."

Foreign Relations Committee Ranking Member Ben Cardin (D-Md.) said he was "saddened" by the chairman's impending retirement. "Our work has been steeped in a love of country and the enduring belief that the foreign policy of the United States should always be conducted in a bipartisan, sober, values-based manner," he said. “Importantly, Bob will still be in the Senate for more than a year and I expect to continue to accomplish a great deal with him as our chairman. Congressional prerogatives and oversight of U.S. foreign affairs are more important than ever as we confront growing global challenges."