He has "written the whole process off," Graham told reporters when asked if he would read newly released transcripts of testimony given by former U.S. envoy to Ukraine Kurt Volker and Gordon Sondland, the U.S. ambassador to the European Union. Democrats released hundreds of pages of testimony on Tuesday that reflected a mixed picture of whether or not President Trump presented a "quid pro quo" of some sort, involving either the release of U.S. military aid or a meeting at the White House.
The transcripts also revealed that Sondland revised his prior testimony to reflect that he told a top Ukrainian official U.S. aid likely wouldn't resume unless the country released a corruption statement. Many Democrats interpreted this as evidence of a quid pro quo.
Of Sondland's revised testimony, Graham said Tuesday: "That's his opinion."
"This, to me, is a manufactured issue created by some unknown whistleblower who needs to be known, and the phone call is the basis for the impeachment allegation," the South Carolina senator continued. "I don’t think the president did anything wrong."
The House of Representatives last Thursday voted largely along party lines to approve a resolution that established "ground rules" for the impeachment inquiry into President Trump, setting the framework for a more public investigation following weeks of closed-door depositions that drew scrutiny from Republicans who demanded more transparency and fairness in the process.
Democrats launched the inquiry following an intelligence community whistleblower complaint about a phone call the president had with his Ukrainian counterpart, Volodymyr Zelensky, over the summer. The complaint accused the president of soliciting a quid pro quo, allegedly threatening to withhold U.S. military aid unless Ukraine investigated former Vice President Joe Biden, his son Hunter and their business dealings in the county.
The White House later released a memorandum of the July 25 Trump-Zelensky call, and it showed that while Trump sought an investigation into the Biden family for corruption, he did not explicitly leverage military aid in order to get Ukraine to investigate.
Fox News asked Graham on Tuesday if he would still say the whistleblower didn't have any credibility, to which the senator replied: "I don't know if they have... credibility or not. I don’t know who they are."
"You shouldn't have an impeachment inquiry that was started by an anonymous allegation," Graham continued. "Whistleblower statutes are designed to protect people from being fired, who report misconduct or corruption. They're not designed to shield the person from being challenged in terms of accusation. So the whistleblower statutes [are] being used unfairly."
He added: "Their biases have to be known if they have any."
White House Press Secretary Stephanie Grisham said in a statement Tuesday that the newly released transcripts showed less evidence for the "illegitimate impeachment sham than previously thought."
While Sondland "presumed" there was a link to the military aid being withheld, he "cannot identify any solid source for that assumption," she added.
Fox News' Jason Donner, Brooke Singman, Adam Shaw and The Associated Press contributed to this report.