Russia has said it is "possible" that its electrical grid is under cyber-attack by the US.
Kremlin spokesman Dmitry Peskov said reports that US cyber-soldiers had put computer viruses on its electrical grid was a "hypothetical possibility".
His comments came in response to a New York Times (NYT) story which claimed US military hackers were targeting Russian power plants.
The report drew scepticism from experts and a denunciation by President Trump.
In its report the newspaper said American "code" had been deployed inside many elements of Russia's power network.
The Times said this was an escalation of other work the US was doing to combat Russian disinformation and hacking campaigns.
Mr Peskov said President Trump had dismissed the allegations made in the Times, calling them "fake news".