Washington (CNN) Sen. Rob Portman, a Republican from Ohio, on Monday criticized President Donald Trump for requesting that Ukraine and China investigate former Vice President Joe Biden, a notable break from the majority of congressional Republicans, who have defended the President or remained silent.

"The President should not have raised the Biden issue on that call, period. It's not appropriate for a president to engage a foreign government in an investigation of a political opponent," Portman told reporters Monday, according to The Columbus Dispatch.

"I don't view it as an impeachable offense. I think the House, frankly, rushed to impeachment assuming certain things," he said.

There is no evidence of wrongdoing by Joe or Hunter Biden in Ukraine. There's also no evidence that the former vice president received any money from China, and a lawyer for Hunter Biden has pushed back on Trump's characterization, calling it "a gross misrepresentation."

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