The United States is planting "digital bombs" in Russia's infrastructure in response to the alleged hacking of last year's presidential election, it has been claimed.
Former President Barack Obama authorised the "implants" of cyber weapons in the final weeks of his Administration and gave US intelligence agencies power to deploy them in retaliation against any future Russian cyber attack, the Washington Post reported.
The covert programme was described as "the digital equivalent of bombs that could be detonated if the US found itself in an escalating exchange with Moscow".
It also emerged that Obama had received a top-secret memo in August, couriered directly to him by the CIA, detailing Russian President Vladimir Putin's direct involvement in cyber efforts to disrupt the election.
The memo contained details of instructions Putin gave to ensure the defeat of Democratic nominee Hillary Clinton, the Post reported.