NATO and the European Union on Thursday vowed to tighten cooperation against the "hybrid warfare" that the West accuses Russia of using in the battle for influence in the former Soviet Union.
NATO has charged Russia with carrying out "hybrid warfare" in the conflict in Ukraine by combining classical military techniques with unconventional guerrilla tactics, as well as non-military means means like cyber-attacks and propaganda.
"Hybrid warfare combines different types of threats, including conventional, subversion and cyber," NATO Secretary General Jens Stoltenberg said after a two-day meeting of the military alliance in the southern Turkish city of Antalya.
The meeting was attended by EU foreign policy chief Federica Mogherini, as the military alliance and the 28-member bloc seek to sharpen their cooperation and intelligence sharing.
Mogherini "and I have asked our teams to intensify NATO-EU cooperation in countering hybrid warfare," Stoltenberg said.
"We will ensure that the strategies we are developing are complementary, so that we can work together quickly and effectively in the case of a hybrid threat against any of our members."
He said the aim of the cooperation is "that in the event of a hybrid threat, there is clarity over who does what."
Western countries have accused Russia of backing and arming separatists in eastern Ukraine and even sending its own forces over the border. Russia denies the charges.
Russia also carried out the annexation of Crimea in 2014 by deploying troops in unmarked uniforms who it only later admitted were members of the Russian military.
But the West has also been deeply critical of the tactics used by Russian media in the Ukraine conflict and accused it of carrying out cyber-attacks as well as saturating social networks with pro-Kremlin trolls.
"We face sophisticated disinformation and radicalization campaigns," said Stoltenberg.
"Our best weapon against disinformation is information, based on our values of democracy, freedom of speech and open societies," Stoltenberg added.
One idea evoked at the meeting was a special trust fund for Ukraine to counter false propaganda. But the suggestion appears far from being finalized.
Mogherini, speaking ahead of the meeting, said the NATO and EU organizations were "different in nature" but facing similar challenges.
"What is extremely important for us is a strong coordination... in particular when it comes to information sharing, when it comes to the new kind of threats we are facing all around us us," she said.
"We [NATO and EU] have challenges around us that unite us. We are different in nature but we share values."
In a nod to criticism that the European Union has been sluggish in responding to situations in its own neighborhood, she said the bloc was "aware we need to increase our capacity to respond to crises."
She emphasized that, in contrast to NATO, "this does not necessarily mean a military approach."
"But we cannot rule out a military aspect of our work," Mogherini added.
Stoltenberg slammed Moscow for its annexation of Crimea and meddling in Ukraine, saying: "To the east, a more assertive Russia has used force to change borders and intimidate neighbors."
"Our security environment has changed and we have to prepare for long lasting change in our security environment."
"When thew world has changed NATO has to adapt," he added.