The review will be handled by the bureau's inspection division and examine the FBI's role in the Flynn probe and determine whether any current employees have engaged in misconduct.
A federal appeals court panel has ordered a trial judge to explain why he is hesitating to grant the Justice Department's request that he dismiss the criminal case against former National Security Adviser Michael Flynn.
But the case has always been a subject of outrage for Mr Trump and his allies, who have alleged that Flynn was effectively set up to lie when agents questioned him at the White House in January 2017.
Flynn pleaded guilty to lying to the FBI about conversations with the Russian ambassador during the presidential transition period, but the Justice Department says its own review of the case determined that there was an insufficient basis for agents to have interviewed Flynn in the first place and that any statements he made to agents were therefore not relevant to the underlying investigation into ties between Russia and Trump's presidential campaign.
Trump has complained publicly about Wray for "skirting" the debate about the FBI's 2016 investigation of possible coordination between Russian Federation and the Trump campaign to influence the election, of which the Flynn case was a part.
Those concerns were given new life earlier this month when the Justice Department moved to dismiss the case and identified a series of what it says were problems in the way Flynn was investigated. Attorney General William Barr assigned U.S. Attorney Jeff Jensen to scrutinize the Flynn case earlier this year.
"T$3 he interview of Mr. Flynn was untethered to, and unjustified by, the FBI's counterintelligence investigation into Mr. Flynn-a no longer justifiably predicated investigation that the FBI had, in the Bureau's own words, prepared to close because it had yielded an 'absence of any derogatory information, '" the department wrote in its filing. The FBI cooperated with Jensen, who after looking over the case materials recommended that the prosecution be dropped. But a former Federal Bureau of Investigation official who worked for Wray suggests this might all be politics.
The Justice Department on May 7 asked U.S. District Judge Emmet Sullivan to drop the charges against Flynn following public pressure from Trump and his political allies.
They stressed that since Justice Department is trying to get the case dismissed after the court had already accepted the plea, Sullivan has "substantial discretion" in how it handles the request that the case be dropped. She also asked the court to take Judge Sullivan off the case, and to vacate his order inviting outside arguments against dismissing the prosecution.