BRUSSELS — After five years of crises, conflicts and deadlines that have come and gone without resolution, Greece and the European countries that have been propping it up financially have come to what they all insist is a final reckoning, with just days to decide whether Greece stays in the euro system or is cast out.

Trouble is, no one seems inclined to be the decider.

With so much at stake for Europe’s long push for deeper integration and the welfare of the Greek people — not to mention the political standing of the leaders involved — both sides have been sidestepping responsibility for the endgame, insisting that what comes next is up to the other.

“The ball is in Greece’s court,” Pierre Moscovici, the European Commission’s senior official for economic and financial affairs, said Wednesday, echoing a theme heard regularly in European capitals and the bureaucracies of Brussels as creditors demand evidence that Greece is willing to take concrete steps to get its finances in order.

But Prime Minister Alexis Tsipras of Greece said the situation was a European problem, in need of a European solution.