They called on the administration "to provide records of interactions with former Director Comey, including any audio recordings".
Mr Trump had earlier in the morning lashed out on Twitter at the news of the special prosecutor, calling the move a politically motivated "witch hunt" by his Democratic rivals.
"I look forward to this matter concluding quickly". "So somebody's going to have to do more than have anonymous sources on this one for me to believe that there's something there".
British PM Theresa May meanwhile said Trump is free to decide what to discuss with White House visitors, while stressing that London's relationship with Washington was "the most important defence and security relationship" around the world.
"(Lavrov) didn't share these secrets with us - neither with me nor with the representatives of the Russian security services.
Adding to the confusion, Russian senator Alexei Pushkov on Wednesday tweeted that "US media were hysterical with Trump because he told us about IS plans to detonate our passenger plane". The Republican billionaire's administration, now just barely four months old, was left reeling by the one-two punch, which sparked instant outrage from Democrats demanding a full explanation.
Trump welcomes Colombia's president to the White House
Mark Warner, D-Virginia, sent a letter Wednesday asking Comey to testify before the committee in both open and closed sessions. President Donald Trump has welcomed the president of Colombia to the White House for their first official meeting.
Comey wrote a memo about Trump's request following the February 14 Oval Office meeting.
But the reports - both rebutted by Trump's team - add to a mounting perception of an administration in a perpetual state of chaos. "I hope you can let this go", Trump said about the investigation into Flynn, according to a memo written by Comey and reported in the Times.
Comey took down their conversation in a memo at the time, according to the New York Times.
OH members of Congress from both political parties praised Wednesday's appointment of former FBI Director Robert Mueller to lead the Justice Department's investigation into Russia's role in November's presidential election. "He is a good guy". "I also got a very, very strong recommendation, as you know, from the deputy attorney general, Rod J. Rosenstein".
The chairman of the House Oversight and Government Reform Committee wants ex-FBI director James Comey to testify before the panel next week.
That raised questions about whether the president improperly attempted to interfere with a federal investigation.