In a speech to European intelligence agencies in Berlin, Andrew Parker said Moscow was using its spies and military to carry out “flagrant breaches of international rules”.
“Bare-faced lying seems to be the default mode, coupled with ridicule of critics,” he said.
“The Russian state’s now well-practised doctrine of blending media manipulation, social media disinformation and distortion, along with new and old forms of espionage and high-levels of cyber attacks, military force and criminal thuggery is what is meant these days by the term ‘hybrid threats’.”
Mr Parker said the Russian government was the “chief protagonist” in trying to undermine European democracies with “malign activities” and their acts risked making it a “more isolated pariah”.
Following the nerve agent attack on former spy Sergei Skripal and his daughter Yulia in Salisbury, Mr Parker said Russia had launched a “cynical and distasteful information campaign”, with at least 30 different “so-called explanations”.
“Whatever nonsense they conjure up, the case is clear,” he said.
He said it was “not acceptable” that the Russian state had carried out the nerve agent attack in Salisbury and supported the Syrian government despite its use of chemical weapons on civilians.
He also criticised Russia’s invasion of Crimea, its bid interfere in elections in the US and France, its attempted coup in Montenegro and the state’s cyber attacks on Western institutions.
Mr Parker, who is director general of the security service, revealed 12 terror plots have been thwarted in the UK since March last year, taking the total number of disrupted attacks in the UK to 25 since 2013.
He said that while Islamic State had lost its “false caliphate” in Iraq and Syria, the terrorist group was “seeking to regroup”.
“Europe faces an intense, unrelenting and multi-dimensional terrorist threat,” he said.
In a nod to Brexit, Mr Parker said co-operation with EU partners was essential to guard against the threats from Islamist militants and Russia.
“We must not risk the loss of mutual capability or weakening of collective effort across Europe,” Mr Parker said.
“We owe that to all our citizens across Europe.”
Meanwhile, a meeting of the Nato-Russia council will discuss for the first time Moscow’s increasing use of “hybrid threats” such as propaganda and disinformation, a senior Nato official said.
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“Nato doesn’t want a Cold War,” said Arndt Freytag von Loringhoven, first assistant secretary general for intelligence and security.
“It wants a constructive relationship with Russia, but it cannot leave unanswered Moscow’s diverse hybrid attacks on democracies of other countries.”