Story highlights Trump discussed tax reform and the opioid epidemic with senators

But not his disagreement with Corker

Washington (CNN) President Donald Trump was largely able to avoid discussion of his bitter feud with fellow Republicans during what appeared to be a unifying lunch with the party's senators on Tuesday.

But minutes after Trump departed Capitol Hill, the junior Republican senator from Arizona, Jeff Flake, excoriated Trump in a floor speech announcing his his retirement from the body.

"We must stop pretending that the degradation of our politics and the conduct of some in our executive branch are normal," Flake said, discarding any appearance of party unity in favor of what he cast as a principled stance against Republican complacency in the face of Trump's presidency.

It was a telling series of events that laid bare Trump's fraught relationship with Republicans, many of whom are caught between their own principles and supporting a President still popular among their base voters.

Those fault lines were apparent earlier Tuesday after an early morning war of words between Trump and the senior Republican on the foreign relations committee.

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