Story highlights Sen. Bob Corker and President Donald Trump have had a tumultuous relationship

Corker's moves to make amends reflect a calculation among many GOP senators

(CNN) Sen. Bob Corker, who is traveling Monday on Air Force One with President Donald Trump, has repaired his relationship with the commander in chief after the two men exchanged fierce words in the fall, sources familiar with their discussions told CNN.

The two have spoken several times since late last year, particularly as Corker was weighing whether to support the sweeping tax overhaul. Ultimately, Corker reversed his position and backed the tax bill -- and endured sharp criticism over what he said was erroneous reporting suggesting he backed the bill because of a provision that would enrich him financially. Corker complained about the news coverage to Trump, who deemed it "fake news," the sources said.

Corker's moves to make amends with Trump reflect a calculation among many Senate Republicans: While they may complain about what they view as his erratic behavior, they will soothe over tense relations and look past previous disputes to get on his good side in order to influence him over key decisions. Sens. Lindsey Graham and Rand Paul, two men who have exchanged bitter words with Trump in the past, have taken similar tacks, which seem to have worked with the transactional President.

For Corker, who serves as chairman of the Senate Foreign Relations Committee, fixing the Iran nuclear deal is a key priority -- one that will require the President's support. As they bonded over the tax bill and their complaints about the media, Corker has been working behind-the-scenes with senior administration officials -- including Secretary of State Rex Tillerson and national security adviser H.R. McMaster -- to make changes to the Iran deal through new legislation in Congress, sources say.

Corker has been working with the Trump administration on the Iran matter even before the two men recently re-engaged and smoothed things over, the sources added.

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