ISIL militants are using the chaos created by the Russian backed military campaign of Bashar al-Assad in Syria to plot attacks against the UK and its allies, the head of MI6 has warned.

In his first major public speech since taking the top job at the Secret Intelligence Service in 2014, Alex Younger, said the continuing war posed a major risk to Britain.

“The scale of the threat is unprecedented. The UK intelligence and security services have disrupted 12 terrorist plots in the UK since June 2013. And MI5 and the police continue to run hundreds of investigations into those intent on carrying out or supporting terrorist atrocities against our citizens,” said Younger.

Since the London attacks in 2005, that killed 52 people, the UK has been largely spared from Islamist inspired terrorism.

However, the MI6 chief, said that Britain also faced a threat from ‘hybrid warfare’ from hostile states attempting to undermine western democracies. Without identifying any country, he said that cyber attacks, propaganda and the subversion of the democratic process represented a fundamental threat to sovereignty.