The Republican leader of the House investigation into Russian interference in the US election announced on Thursday he was stepping aside after being criticised for compromising the probe in visits to the White House.
Devin Nunes, the chairman of the House Intelligence Committee, had come under fire for briefing President Donald Trump on top secret intelligence reports he had viewed while keeping members of his own committee in the dark.
He was strongly criticised by Democrats on the committee for compromising the investigation by meeting with Trump and other White House officials who were potentially targets of the probe.
The committee's work had ground to a halt amid charges and counter-charges of politicising the issues.
Nunes also became the target of a complaint to Congress' ethics committee for revealing some of the content of those intelligence reports, which he alleged showed that members of the previous Obama administration were abusing their powers to spy on Trump and his advisers.
Nunes said he was stepping aside temporarily to address the ethics complaint.
"The charges are entirely false and politically motivated, and are being levelled just as the American people are beginning to learn the truth about the improper unmasking of the identities of US citizens and other abuses of power," he said in a statement.
Nunes said Republican Representative Mike Conaway would now lead the committee's investigation.