Professor Takis Tridimas:

I understand "to take steps to prevent" to be a wider obligation and it is a positive obligation. As a matter of EU law, there are cases where the European Court of Justice has held that the protection of fundamental rights creates positive obligations on the member states, for example, positive obligations to prohibit or punish torture. That is the situation as far as the case law of the European Court of Justice is concerned. My understanding of the opinion of the International Court of Justice is that positive steps should be taken. Perhaps, though, I can defer to our international law experts here.