The White House on Monday said Donald Trump would not use presidential powers to prevent ex-FBI director James Comey from testifying to Congress.
"President Trump will not assert executive privilege regarding James Comey's scheduled testimony," the White House said in a statement.
That ended speculation that Trump may try to block potentially explosive Comey testimony on Thursday.
Trump fired Comey early last month as the FBI was investigating possible collusion between Trump's campaign and Russia to tilt the election in the Republican's favor.
Comey is expected to be questioned about the circumstances of his firing and allegations that Trump has tried to stifle the agency's Russia investigation and divert attention to intelligence leaks that have hurt his administration.
His hotly awaited appearance on Capitol Hill comes as probes by the Justice Department and several congressional committees have focused on Trump's inner circle, with investigators said to be examining contacts between top White House adviser and Trump son-in-law Jared Kushner.
"The president's power to assert executive privilege is well-established," the White House said in a statement, adding that Comey's testimony would "facilitate a swift and thorough examination of the facts."
The White House had floated the idea that Trump could invoke executive privilege, to protect the confidentiality of presidential discussions.
But some aides were wary that it could look too much like a White House cover-up.