THE invasion of Ukraine by Vladimir Putin was unlikely to have been preventable – but many did not believe he would launch a full-scale attack, according to experts.

Phillips O’Brien (below), professor of ­strategic studies at St Andrews ­University, said while the West could have acted sooner, it would have been unlikely enough to deter the action taken by Russia.

He said: “To Putin, his vision of Ukraine is not as an independent state – he said Ukraine should be part of Russia, he is trying to get it back to a Russian Empire.

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“So I don’t see you could have ­prevented [the action], unless Ukraine literally agreed to its own destruction.

“I know people say you should have done more, quicker, but that is not the way these things often work. There were negotiations going on and you don’t want to give a pretext for them to say that they will invade.

“If you have sanctions they may say well why not invade then. I think it might have been good to talk about it earlier, but it is not so easy to do.”

Western nations have now ordered a series of sanctions with the latest target the assets of Putin and his

Foreign Minister Sergei Lavrov, which will be frozen in the US, EU, UK and Canada.

The EU’s latest round of sanctions also target Russian elites and make it harder for its diplomats to travel, while UK sanctions have been aimed at Russian banks and oligarchs.

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However, O’Brien said the real ­impact would come from “rooting out” the Russian money which has flowed into countries such as the UK.

“What they are now making it ­difficult to do is to move money around and things like that, but over the last few years they have accepted so much capital here that it is very hard to stop it,” he said.

“The real thing to do would be to start seeing where the money has gone in the UK and all the other countries, and find a way to try to confiscate it.

“But that is not easy to do. [It is in] flats in London, probably flats in places like Glasgow and Edinburgh.”

O’Brien said he believed the ­invasion of Ukraine was harder than Putin expected and even if he wins a military victory it had “weakened him considerably”.

He compared the actions of Putin to the invasion of Poland by Hitler in 1939, which triggered the start of World War Two.

O’Brien added: “In the post Cold War world in Europe, we did have events in the Balkans but we didn’t have this full state intervention.

“I just don’t think we believed it would happen – I believed he wouldn’t do this as it is too much of a threat to his rule.

“My general feeling was he might go for pockets [of Ukraine], he might go for the East, but not this massive full-on invasion. This is in my mind weakening his rule.”

Dr Huseyn Aliyev (below), lecturer in Central and East European studies at Glasgow University, echoed this view saying there had been “general disbelief” in expert circles that Russia would stage a full-scale invasion.

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“Most likely this has been in preparation for quite a few months and it is not very likely that something could have prevented it,” he said.

“Possibly if the West was ­willing to accept Russia’s ­unrealistic conditions on Nato and ­non-enlargement. But both Putin and Western countries knew very well this is not something that could have been achieved.

“[Putin] knows very well his ­demands will not be met and his ­demands are unfeasible – he was ­preparing for this outcome for quite a long time.”

Aliyev said the outcome of the coming days of war and whether ­Russia achieves its military aims would determine what happens next. But he said the opinion of the Russian population about the action being taken by their President is unlikely to have any influence on Putin.

“There was a recent survey among the Russian public that found over 70% of Russians do not support military action in Ukraine,” he said.

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“We don’t know how reliable the figures are, but we have seen large protests taking place across ­Russia and clearly there are thousands more who disagree with this policy and who mistrust the Kremlin. The ­rising number of casualties in the war that Russia is currently ­sustaining is ­certainly likely to increase discontent in Russia. So we will probably ­witness even more discontent over the coming days and weeks.”

But he added: “It has probably been over 15 years since Putin ­completely stopped caring about the public ­opinion of the Russian population. He suppresses any protests or demonstrations criticising his policies.

“He will be absolutely immune to anything on the ground in Russia in terms of public discontent.”