Nigel Farage intensified his attack on the EU's "vanity" foreign policy on Thursday as he accused Brussels of poking the "Russian bear with a stick" over Ukraine and of deepening the Syrian civil war by giving false hope to forces hoping to topple the Assad regime.

Amid widespread criticism of the Ukip leader's claim in his TV debate with Nick Clegg that the EU had "blood on its hands" after the violence in Kiev, Farage said the EU had destabilised a series of countries.

The Ukip leader went on the offensive after political leaders expressed astonishment at his claim in the debate with the deputy prime minister that the EU was to blame for the bloodshed after giving false hope to people in western Ukraine when it offered a partnership agreement to the ousted president, Viktor Yanukovych.

The deputy prime ministerClegg said he was "extraordinarily surprised" that the Ukip leader had allowed his "loathing of the EU" to prompt him to say in their televised LBC debate that the EU had blood on its hands in Ukraine.

Lord Ashdown, the former Liberal Democrat leader, accused Farage of having given comfort to Putin. The Tories said the remarks by Farage in the final minutes of his hour-long LBC debate with Clegg, after the deputy prime minister had bombarded him with statistics about the EU, raised questions about his stamina.

Speaking on his weekly LBC phone-in on the morning after their debate, Clegg made clear thathe would highlight the remarks by Farage when they hold a second televised debate on BBC2 next week.

He said: "It shows quite how extreme people can be – like Nigel Farage – when their loathing of the EU becomes so all-consuming that they even end up siding with Vladimir Putin in order to make their point. To suggest that somehow it is the EU's fault that the Ukrainian people rose up, as many did on the streets of Kiev, against their government seeking to claim greater democracy, greater freedom, is such a perverse way of looking at things."

But Farage issued a statement on Thursday night attacking the "vanity" of EU foreign policy and extending his criticism beyond the EU's handling of Ukraine. He said: "We are seeing vanity take the place of reason in foreign policy and the result is to destabilise a whole series of countries to no positive effect that I can discern.

"It is not just the Ukraine. The civil war in Syria was made worse by EU leaders stoking the expectation of western forces helping to topple the Assad dictatorship despite the increasing dominance of militant Islamists in the rebellion."

Farage insisted he did not support Putin but accused the EU of "feeding an entirely unrealistic dream of a future as an EU member state" to Kiev. He added: "This has encouraged brave young men and women in western Ukraine to rebel to the point of toppling a legitimate president and led to the utterly predictable debacle whereby Vladimir Putin has annexed part of the country and now casts a long shadow over hopes of genuine democracy in the rest of it...If you poke the Russian bear with a stick he will respond. And if you have neither the means nor the political will to face him down that is very obviously not a good idea."

The Ukip leader was disowned last night by a European commentator who accused the EU earlier this month of having "made almost every strategic mistake possible in its handling of the Ukraine file".

Jan Techau, director of the Carnegie Europe thinktank, told the Guardian: "It is an extremely cynical argument by Mr Farage. You can blame the EU rightly for not having calculated correctly the strategic considerations of Mr Yanukovich and Mr Putin. We were all a bit naive there. But this does not amount to a whipping-up of the population so that they would then run into a trap. This is not about abandoning them.

"The ones that have caused the bloodshed were the Russians. What enrages me about [Farage's remarks] is that it actually turns the victims into culprits. That is a very cynical argument. It completely disqualifies him from any kind of foreign policy judgment."