Bob Corker: Donald Trump has 'debased our nation', says Republican Senator in unprecedented attack

The spat between the two Republicans precedes a lunch in the Capitol where Mr Trump is expected to encourage party unity

Republican Senator Bob Corker has suggested Donald Trump is unfit for office and refused to say he trusts him with the nuclear codes, in an extraordinary series of denunciations of the President.

"I don't know why he lowers himself to such a low, low standard and debases our country," Mr Corker told CNN during an interview in the Capitol, marking an escalation in the rhetorical fight between the two. "He is obviously not going to rise to the occasion as President of the United States."

During the startling barbs, the Republican, who endorsed Mr Trump for president in 2016, said that he wouldn't make that same decision twice.

"No way," Mr Corker said when asked about supporting the President again. He said that Mr Trump isn't even a good role model for the nation's children: "No, absolutely not."

Wrapping up the interview, Mr Corker refused to say that he trusts Mr Trump with the nuclear codes, a grave responsibility held only by the President.

"I don't want to carry this much further, but I expressed concerns a few weeks ago about his leadership... and nothing has changed," Mr Corker said. "I don't want to make it a daily thing."

The comments came amid a flurry of attacks on Mr Corker by Mr Trump, who has charged that the Republican is only opposing him because he didn't support him for reelection. Mr Corker announced earlier this year that he will retire at the end of his current term, saying that he prefers the citizen legislator model to serving in the US Senate.

"Bob Corker, who helped President Obama give us the bad Iran Deal & couldn't get elected dog catcher in Tennessee, is now fighting Tax Cuts," Mr Trump wrote on Twitter. "Corker dropped out of the race in Tennessee when I refused to endorse him, and now is only negative on anything Trump. Look at his record!"

Mr Corker is the chairman of the Senate foreign relations committee, a prominent position he used to vocally oppose the Iran nuclear agreement negotiated by the Obama administration. While the Republican voted against approving the deal, and had pushed for legislation that would give Congress greater oversight on such deals, Mr Trump has attempted to paint the senator as a strong supporter of the nuclear agreement that released sanctions on Iran in exchange for Iran's cooperation with international nuclear oversight.

"Senator Corker is the incompetent head of the Foreign Relations Committee, & look how poorly the US has done," Mr Trump tweeted following Mr Corker's remarks. "He doesn't have a clue as the entire World WAS laughing and taking advantage of us. People like liddle' Bob Corker have set the US way back. Now we move forward!"

Mr Trump is scheduled to head to the Capitol later Tuesday for a lunch with Republicans, where he is expected to push for party unity.

That charge for unity comes after a series of embarrassing failures to repeal and replace Obamacare, a promise that Republicans have been making for seven years. With those legislative defeats behind them, Mr Trump and republicans in Congress are looking toward passing tax reforms.

The current tax deal being paraded in front of Republicans in Congress would cut taxes primarily for the wealthy in America, offsetting that funding loss with massive cuts to Medicare and Medicaid. Those programs, which would lose nearly $1.5 trillion in funding over the next decade, would primarily effect low-income Americans and senior citizens. Those cuts could have dramatic effects, too: Medicaid provides a lifeline for over 70 million Americans, including children, the disabled, and senior citizens. That program, for instance, covers 60 per cent of those in nursing homes in America, meaning that some seniors could see their benefits slashed under the tax plan.