WASHINGTON (AP) — A prominent Republican senator delivered a stinging rebuke Thursday of Donald Trump’s short time in office, declaring he has not shown the stability or competence required for an American president to succeed.

Sen. Bob Corker of Tennessee, chairman of the Foreign Relations Committee, also said Trump “recently has not demonstrated that he understands the character of this nation.” During comments to local reporters after a speech to the Chattanooga Rotary Club, Corker called for “radical changes” in how the Trump White House operates.

Separately, Republican Sen. Tim Scott told a newspaper in his home state of South Carolina that Trump’s heavily criticized response to violence in Charlottesville, Virginia, “complicates this administration’s moral authority.”

Corker’s remarks, which were posted on Facebook, came two days after Trump declared at a New York press conference that white supremacists don’t bear all the blame for the melee in Charlottesville, where a woman was killed after being struck by a car driven into a crowd. Trump triggered a firestorm of protest, with a number of Republicans criticizing him for giving weight to the complaints of white nationalists by refusing to definitively condemn them.

Corker has sought to be a strong supporter of Trump’s, particularly on foreign policy matters. He was considered as a candidate for secretary of state in the Trump administration before Rex Tillerson, the former chief executive officer of Exxon-Mobil, was picked for the job.

But Trump’s impulsive and often bombastic style has complicated the relationship for Corker and other congressional Republicans. A few months ago, following reports that Trump had disclosed highly classified information to a pair of Russian diplomats in the Oval Office, Corker said the White House was “in a downward spiral.”

But Corker in recent weeks had largely declined to answer questions about Trump’s tweets or other political drama, telling reporters covering Congress that he was focused instead on matters of policy.

He elected to weigh in Thursday, however. Noting that the country is polarized, Corker said, “Helping inspire divisions because it generates support from your political base is not a formula for causing our nation to advance, our nation to overcome the many issues that we have to deal with right now.”

Corker said, “The world needs for our president to be successful,” and said he’s hopeful Trump will do what’s necessary to bring out the best in people, regardless of their political affiliations.

Trump, he said, needs “to take stock of the role that he plays in our nation and move beyond himself, move way beyond himself, and move to a place where daily he’s waking up thinking about what is best for our nation.”

Corker also defended his Republican colleague, Sen. Jeff Flake of Arizona. On Twitter Thursday, Trump called Flake “toxic” while praising his primary election opponent.

Flake is “one of the finest best human beings I’ve ever met,” Corker said. He said the White House would be well served to embrace Flake because of his substance and character. Flake has a “conscience and is a real conservative,” according to Corker.

Scott is the Senate’s only black Republican. He told The Post and Courier of Charleston that Trump erred by drawing a “moral equivalency” between the white supremacists and counterdemonstrators in Charlottesville.

“I think you are either missing four centuries of history in this nation or you are trying to make something what it’s not,” Scott said.

Trump’s controversies have compromised the GOP’s ability to get things done on health care, taxes and financial regulations and have put Republicans in a “precarious position,” Scott told the newspaper.WHAT OTHERS ARE CLICKING ON:

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