By Manu Raju, CNN Senior Congressional Reporter

(CNN) -- Tennessee Sen. Bob Corker, the influential chairman of the Senate foreign relations committee who was once considered for a spot in President Donald Trump's Cabinet, is weighing whether to call it quits next year.

Corker told CNN last week that he has not made a decision about his future, and appeared to confirm Trump's tweet that he asked the President for political advice about whether to run for reelection.

"As far as what am I going to do in the future, I'm still contemplating the future," Corker said in an interview. "It's a tremendous privilege to do what I do, and to weigh in on the big issues. ... But I have not decided what I'm going to do in the future."

If Corker, 65, were to retire, it'd be a huge surprise in the Senate given his perch sitting atop a powerful committee, his alliance with the Senate leadership and the fact that he's only in his second term. Plus it would give Democrats a new shot to pick up another Senate seat, although it still would be an uphill climb given that the state is still a solid GOP stronghold.

A source familiar with Corker's thinking said the Republican is legitimately torn about whether to remain in the body another six years or to return to his roots in the business sector.

But the source said Corker is taking steps to prepare for a run, raising money for a bid with more than $7 million in cash on hand. Plus, he's hired a seasoned political operative as a general consultant, Ward Baker, who led the GOP's Senate campaign committee in the party's successful 2016 election cycle.

Still, it's unclear to people close to Corker whether he will run or call it quits -- or when he will make a final decision. And, the source said, the senator has spoken to many people about his deliberations, including Senate Majority Leader Mitch McConnell, who is urging him to run again.

Corker came into the spotlight in August, when he sharply criticized Trump in the aftermath of the President's handling of the deadly violence during a white supremacist rally in Charlottesville, Virginia.

At the time, Corker said: "The President has not yet, has not yet been able to demonstrate the stability nor some of the competence that he needs to demonstrate in order to be successful. And we need for him to be successful. Our nation needs to be successful."

Corker added: "He has not demonstrated that he understands what has made this nation great and what it is today."

Asked last week if he still stood by that sentiment, Corker told CNN: "I don't make comments like the ones I've made without thinking them through in advance."

The sharp rebuke in August set off a torrent of criticism from the White House, with press secretary Sarah Sanders calling it a "ridiculous and outrageous claim" at the time and Trump tweeting about the episode.

"Strange statement by Bob Corker considering that he is constantly asking me whether or not he should run again in '18," Trump tweeted. "Tennessee not happy!"

Asked about that tweet, Corker said: "I thought his tweet was fine."

Corker said he's had "multiple interactions" with senior officials at the White House since the flap, and said "no question my relationship is just the same as it was before."

During the campaign, Trump considered Corker as a running mate, and the senator was later a finalist for secretary of state before the President chose Rex Tillerson.

Asked if he had spoken with the President about his election plans, Corker said he believed the topic came up when they played golf together.

"Oh, I mean, I talk to the President about almost everything," Corker said. "We spend a lot of time together. We play golf. We, you know, they talked to me about being potentially vice president, secretary of state, so I've had multiple conversations about the future with lots of people. So, I'm sure when we played golf, the topic came up."