As the European Union’s impasse over its supposedly imminent Russian oil embargo stretched into days and then weeks, one ambassador quoted Samuel Beckett’s play "Waiting for Godot” to his colleagues: "Nothing happens, nobody comes, nobody goes, it’s awful!”

Diplomats and officials are getting increasingly frustrated the EU may already be reaching the limits of the short-term pain it can inflict on Russia three months after its invasion of Ukraine.

Member states are failing to deliver on promises to hit President Vladimir Putin where it hurts: the lucrative energy industry. The focus has been on Hungary’s refusal to back sanctions, but other countries are yielding to Putin’s demands for gas payments in rubles.