His secretary of state, Mike Pompeo, had said on Friday evening that Russia was “pretty clearly” responsible for the attack, which is believed to be among the most serious on record.
According to reports on Thursday, several US government agencies were targeted by the cyber attack, which compromised sensitive information for months, reports suggest.
White House officials drafted a statement on the security breach and were preparing to release it on Friday afternoon, but were told to stand down, according to sources who spoke to CNN.
The statement would have placed blame on Russia for coordinating the attack but, according to the sources, was open to other actors being involved in the security breach.
It was not clear to them why the statement was blocked by the Trump administration.
The president went on to dismiss reports about the cyber attack on Twitter on Saturday, in remarks that contradicted Mr Pompeo, who had said Russia was responsible
It was neither clear if Mr Pomepo was aware that the White House had pushed back on the planned statement, before his remarks.
“The Cyber Hack is far greater in the Fake News Media than in actuality. I have been fully briefed and everything is well under control,” wrote Mr Trump.
“Russia, Russia, Russia is the priority chant when anything happens because Lamestream is, for mostly financial reasons, petrified of discussing the possibility that it may be China (it may!).
The Cyber Hack is far greater in the Fake News Media than in actuality. I have been fully briefed and everything is well under control. Russia, Russia, Russia is the priority chant when anything happens because Lamestream is, for mostly financial reasons, petrified of….
— Donald J. Trump (@realDonaldTrump) December 19, 2020
The attack, which Reuters reported last week, was said to have breached computer systems at multiple government agencies who used software called Solarwinds, which was infiltrated by hackers.
The Departments of Agriculture, Commerce, Energy and State – as well as the cybersecurity arm of the Department of Homeland Security – were among those whose systems were breached, CNN reported.
Mr Pompeo said in an interview with radio talk show host Mark Levin, that “This was a very significant effort and I think it’s the case that now we can say pretty clearly that it was the Russians that engaged in this activity”.
The White House has been contacted for comment by The Independent.