National Grid is under threat of a significant cyber attack by extremist group Isis, as part of its plot to target UK infrastructure.

The stark warning will be made by Chancellor George Osborne later today, according the Telegraph, alongside a pledge to double Government spend on cyber security to £1.9 billion by 2020.

The newspaper reports that Osborne will use a speech at the Government Communications Headquarters (GCHQ) to warn of growing concerns that terror attacks against the UK by Isis could target National Grid, power plants and hospitals.

Osborne is expected to say that the terror group are “already using the internet for hideous propaganda purposes; for radicalisation, for operational planning too.”

“They have not been able to use it to kill people yet by attacking our infrastructure through cyber attack. They do not yet have that capability. But we know they want it, and are doing their best to build it,” Osborne will say.

The warning comes after multiple terror attacks in Paris late on Friday. Since April Isis has claimed responsibility for attacks on Kenya, Nigeria, Sharm el-Sheikh and Beirut.

Prime Minister David Cameron said in the wake of the Paris attack that the UK foiled a major plot targeting the UK in recent weeks and is currently investigating 600 possible terror plots and counter-terrorism cases.

The almost £2 billion cyber security push is the second government move in recent weeks to protect the UK’s energy infrastructure against cyber-terror.

Last month it emerged that Chinese-built nuclear power plants in the UK will be protected from the threat of a cyber-attack by a listening station operated by GCHQ.

According to The Times, China is still seen as a serious threat to British interests, especially in cyberespionage, and the station will allow British spies to monitor computer systems at Chinese-built nuclear plants to prevent possible cyber-attacks, if diplomatic relationships between the UK and China were to break down.

National Grid said it has “robust monitoring systems” in place and keep the IT systems used to operate the gas and electricity networks isolated from its everyday business systems to ensure the networks remain safe and reliable.