An expert has told RTE's Prime Time that sanctions imposed against Russia by the West will not stop Russian President Vladimir Putin as he moves troops into Ukrainian territory.
Dr Alexandra Vacroux of Harvard's Davis Center for Russian and Eurasian Studies said she is doubtful that the sanctions announced will impact Putin's advances.
She said: "The sanctions are not going to stop the Russians. One of the things that Putin said in his speech yesterday is that 'you're going to sanction us no matter what.' So it makes no difference what we do.
"They are not really a deterrent anymore – they are punishment and, because they are punishment, we still have to impose them. But they are not going to change Russian behaviour in terms of the impact on Russia."
However, Dr Vacroux said an alternative sanction could grab Russia's attention.
She said excluding Russia from the Swift messaging system, used by banks to transfer money to other financial institutions, could have an impact.
"If Russia is kicked out of that, the way Iran was, that could be a very severe blow to their economy."
She added: "Russia's big leverage is the fact that they are supplying so much oil and gas to Europe. It's cold, and now is an excellent time to reduce gas supplies.
"The other thing they could do is a cyberattack on some of the infrastructure, both in Europe and in the United States.
"We know from the SolarWinds attack last year, and also the shutdown of the Colonial pipeline is that they have already put in a lot of malware into our infrastructure systems in the West. And it's just a question of them activating it in order to disable some of our key infrastructure."
Dr Vacroux also told the programme that a minor war between the two countries was "inevitable" but said a question remained whether the fighting would spill over into other Western countries.
She said: "The big question is whether this war could spread beyond just Russian and Ukrainian troops. To some extent, that depends on whether NATO is so concerned about what the Russia plans to do.
"For example, if they plan absorb Ukraine completely that they would then decide that NATO troops need to go into Ukraine, into the theatre and fight the Russians."
