Speaking Thursday, Kremlin spokesman Dmitry Peskov refused to be drawn on whether the alleged hacks were the work of government or non-government actors.
"Hacking attacks that are being carried out from the territory of the United States are recorded every day. Including attacks on the president's website. It's true," Peskov told reporters.
Asked if his information indicated the attacks were carried out by intelligence agencies or unaffiliated hackers, Peskov said, "I wouldn't like to amuse the public by saying that official Washington is behind it. A hacking attack carried out from the territory of some country cannot mean that the authorities have anything to do with it."
State Department Spokesman Heather Nauert said the Russian claim "does not surprise me" and dismissed it as "propaganda." Messages left with the National Security Agency and White House were not immediately returned Thursday.
Peskov's statement comes hours before Comey appeared before the Senate intelligence committee in one of the most eagerly awaited hearings in decades.
He followed through on expectations that he would publicly contradict aspects of US President Donald Trump's accounts of their private conversations, characterizing some of the president's comments as lies.
His testimony represented a pivotal moment in the saga of Russian election hacking and alleged collusion
by Trump aides that has cast a dark shadow over the opening months of the new administration.
Comey faced questions about whether Trump abused his power in demanding loyalty from the former FBI chief. He was also grilled on claims the President obstructed justice by asking him to shut down part of the bureau's Russia probe.
But while the US appears to be gripped by the case, Peskov insisted Moscow will not be paying much attention to the hearing in Washington.
"We are much more interested in the summit of the state leaders of Shanghai Cooperation Organization which takes place in Astana today and tomorrow," Peskov added.
Russian President Vladimir Putin is attending the Astana meeting.