Western nations are battling a surge in Russian hacking activity as Vladimir Putin’s cyber troops set their sights on critical infrastructure, GCHQ chiefs have warned.

Cabinet Office minister Oliver Dowden said Russian-aligned hackers want to “disrupt or destroy” critical infrastructure such as power stations.

He added: “These are fringe state threats – the cyber equivalent of the Wagner group – and initially these groups focused their attacks on Ukraine and the surrounding region.

“But recently, they have begun to turn their attention to the UK and its allies.”

Criminal hacker groups in Russia have increasingly been targeting Western countries in recent months, especially NATO members supporting Ukraine.

Experts say that “patriotic” young Russians are carrying out cyber attacks against Western organisations and businesses.

Paul Chichester, the NCSC’s operations director, said: “From our tracking and understanding of the Russian cyber ecosystem, we're certainly seeing individuals and groups who are more on that edge between cybercrime and patriotic hacking.”

“They’re taking that interest and having those conversations around just how they can use those skills to pursue what they believe are patriotic aims.”

NCSC bosses have issued a formal warning to critical national infrastructure operators to caution them about the renewed threat.

Lindy Cameron, chief executive of the NCSC, said: “If the UK is to be the safest place to live and work online, then resilience must urgently move to the top of our investment shopping list.”

The warnings come after an investigation alleged that Russia has a programme to sabotage wind farms, gas pipelines and power cables in the North Sea.

Public broadcasters in Denmark, Norway, Sweden and Finland reported that Russia was using disguised ships to carry out underwater surveillance and map key sites for possible disruption.

GCHQ’s security arm also warned of an expansion in mercenary hacker-for-hire operations, in which highly skilled cyber companies offer their services to the highest bidder.

Around 80 countries are believed to have bought commercial spyware in what the NCSC described on Wednesday as a “transformational” leap in the volume of surveillance they could carry out on dissidents, political opponents and the media.

“Spyware has almost certainly been used by some states in the targeting of journalists, human rights activists, political dissidents and opponents and foreign government officials,” the NCSC’s alert said.

Britain aims to shame other countries that either allow such spyware companies to operate or which buy their products for their own uses.

Ms Cameron added: “What I like is that we're seeing the culture change internationally. It’s becoming more embarrassing to be a state harbouring this kind of capability.”

One example of a commercial spyware company is Israel’s notorious NSO Group, which created an iPhone hacking tool called Pegasus.

Pegasus was used by the Saudi Arabian government to silently snoop on the phone of dissident journalist Jamal Khashoggi.

Mr Khashoggi was murdered and then dismembered after being induced to visit the Saudi embassy in Istanbul.

“The sophistication of some commercial intrusion cyber products and services can almost certainly rival the equivalent capabilities of some state-linked Advanced Persistent Threat (APT) groups,” the NCSC said.

APTs are advanced hacker groups that are normally operated by governments.