At the daily White House press briefing, Deputy Press Secretary Sarah Huckabee Sanders told reporters the president wants a "thorough investigation of facts", in reference to Comey's testimony before the Senate Intelligence Committee this Thursday.
Senators will nearly certainly ask Comey whether Trump asked him to drop an Federal Bureau of Investigation probe into Flynn's contacts with Russian government officials.
White House: Trump won't stop Comey from testifying
Comey will appear before the Senate intelligence committee on Thursday, with lawmakers seeking answers as to whether he believes the President sought to obstruct his Russian Federation probe or demanded his loyalty before he fired Comey. Comey's conversations and meetings with Trump were memorialized in memos written by the former Federal Bureau of Investigation director.
The Russia investigation is expected to be a key part of Comey's high-profile testimony on Thursday. Comey was subsequently fired by Trump in May.
Comey's testimony will be the first public remarks since he was summarily fired by Trump in early May, and represent a moment of great peril for this already embattled president.More news: Van strikes pedestrians on London Bridge
Associates of Comey said the former director kept notes of his conversations with Trump, including of a February meeting in which the president asked Comey to lay off an ongoing investigation into former national security adviser Michael Flynn - a topic that is sure to come up at the hearing.
Asked at a news conference if he pressured Comey to drop the Flynn probe, Trump had said, "No. No".
Mueller has reportedly met with Comey to discuss the parameters of his testimony.More news: Nadal Cruises into Third Round, 74-2 at Roland Garros
White House press secretary Sean Spicer said Friday the decision by the White House counsel's office hasn't been made yet.
The investigation into ties between the Trump campaign and Russian officials is also scaring off people who had been on the fence about joining the administration.
The online news outlet said the NSA report depicted a hacking operation tied closely to Moscow's GRU intelligence directorate that targeted private USA companies providing voter registration services and equipment to local governments around the country.More news: Liberum Capital Reiterates "Hold" Rating for QinetiQ Group plc (QQ)