UK Defence minister Michael Fallon on Thursday accused Russia of "weaponising misinformation", in a stark warning on cyber warfare in which he also took aim at Kremlin-backed media.

"Today we see a country that in weaponising misinformation has created what we might now see as the post-truth age," Fallon said during a speech at the University of St Andrews in Scotland.

"Russia is clearly testing NATO and the West. It is seeking to expand its sphere of influence, destabilise countries and weaken the alliance," he added.

The defence minister's comments follow allegations by US intelligence agencies of interference in the country's elections by Moscow, which prompted the outgoing administration to impose sanctions on Russian agencies.

Fallon referred to the allegation in describing a "persistent pattern of behaviour" by Moscow.

He drew on other cases linked to Russia such as a 2015 cyber attack on the German parliament, warning of possible future interference in Germany's elections later this year.

"(Russia) is undermining national security for many allies and the international rules-based system.

"Therefore it is in our interest and Europe's to keep NATO strong and to deter and dissuade Russia from this course," said Fallon, who also called for London to engage with Moscow.

His remarks come after NATO chief Jens Stoltenberg last month said there was a monthly average of 500 "threatening cyber attacks" against the military alliance's infrastructure in 2016, an increase of 60 percent on the previous year.

Echoing Stoltenberg's calls for greater focus on cyber security, Fallon said: "NATO must defend itself as effectively in the cyber sphere as it does in the air, on land, and at sea so adversaries know there is a price to pay if they use cyber weapons."

The minister also took aim at Kremlin-backed media, such as television channel RT and Sputnik news agency, which he said were responsible for spreading "Soviet-style misinformation".

In December the European Parliament approved a motion condemning the outlets for disseminating "absolutely fake" news.