The Obama administration has suggested that Russian President Vladimir Putin personally authorised the hacking of email accounts belonging to officials in the Democratic party in the run-up to the presidential election.
The White House also assailed Mr Trump himself, saying he must have known of Russia’s interference, although no proof was offered for any of the accusations.
The Kremlin flatly rejected the claim of Mr Putin’s involvement, with Putin spokesman Dmitry Peskov dismissing it on Thursday as “laughable nonsense.”
Kellyanne Conway, Mr Trump’s senior transition adviser, said it was “breathtaking” and irresponsible that the White House had suggested Mr Trump knew Russia was interfering to help his campaign.
That led Obama spokesman Josh Earnest to unload on Thursday, arguing that Mr Trump, who has dismissed the CIA’s assessment of Russian interference, should spend less time attacking the intelligence community and more time supporting the investigation that Mr Obama has ordered.
Earnest said it was “obvious” Mr Trump knew what Russia was doing during the campaign, pointing out that Mr Trump had encouraged Moscow during a news conference to find Ms Clinton’s missing emails.
Mr Trump has said he was joking.
“I don’t think anybody at the White House thinks it’s funny that an adversary of the United States engaged in malicious cyber activity to destabilise our democracy. That’s not a joke.”
White House spokesman Josh Earnest
US intelligence officials have linked the hacking to Russia’s intelligence agency and its military intelligence division.
Moscow has denied all accusations that it orchestrated the hacking of email accounts of Democratic Party officials and Ms Clinton’s campaign chief, John Podesta, and then leaked them to WikiLeaks.
Democrats pounced on the latest suggestions of Mr Putin being connected to the daily release of emails during the presidential race from some of Ms Clinton’s closest advisers.
Mr Putin was “clearly involved,” said outgoing Senate Minority Leader Harry Reid.
“Having been the former head of the KGB, does that surprise you?” Reid said. “And does it surprise anybody today when he denied it?”
Secretary of State John Kerry said he wouldn’t comment on whether Mr Putin was involved.
“People need to remember that the president issued a warning,” Secretary Kerry said.
“But he had to be obviously sensitive to not being viewed as interfering on behalf of a candidate or against a candidate.”