"It's a disgrace what's happened with respect to the things that were done to our country," Trump told reporters at the White House Monday afternoon. "It should never again happen to another president."
He called the report's findings "an embarrassment" and "dishonest" and said it was "a very sad day."
The Justice Department's internal watchdog found the Russia investigation was not improper, despite significant allegations of wrongdoing in how agents handled the counterintelligence probe of Trump's presidential campaign.
But despite Trump's claims, the report did not vindicate months of allegations Trump and his allies made about the origins of the FBI's investigation. Rather, the department's inspector general exonerated FBI leadership of the president's accusations they were engaged in a conspiracy to sabotage his campaign.
Despite the findings, Trump labeled the investigation an "attempted overthrow" of the government.
"It was concocted, and you say what you want, that was probably something that's never happened in the history of our country," Trump said.
In an exclusive broadcast interview with ABC Justice Correspondent Pierre Thomas, FBI Director Chris Wray said he did not think the agency had treated the Trump campaign unfairly.
Even as the president sought to characterize Monday’s findings as a bombshell, he also teased a separate, forthcoming report from a U.S. attorney appointed by Attorney General William Barr to look at the conduct of intelligence agency officials who initiated the counterintelligence investigation of the Trump campaign.
The attorney, John Durham, said in a statement Monday that even though his investigation was ongoing, based on the evidence his team had collected so far, "last month we advised the Inspector General that we do not agree with some of the report’s conclusions as to predication and how the FBI case was opened."
Trump said Monday that he believed Durham's report would prove more significant.
"I look forward to the Durham report, which is this information plus plus plus," he said. "I’m going to put this down as one of our great achievements."