The talks foundered over opposition to Italian Foreign Minister Federica Mogherini's candidacy for the foreign policy role and demands by central and east European leaders that the job should go to someone from their region, diplomats said.
The leaders did agree to step up sanctions against Russia over separatist violence in eastern Ukraine, shortly after Washington also tightened the screws
German Chancellor Angela Merkel said Moscow had failed to fulfil commitments to restore peace in the region.
"Of course it is a deepening of the economic sanctions, indirectly the listing of individuals were already economic santions, but it is a deepening of that. Now we can have a discussion on stage two or three, but that is not relevant in my eyes. But we are entering the economic sphere here," she said.
The EU will expand sanctions against Russia to target companies that undermine Ukrainian sovereignty and will ask the EU's European Investment Bank and the European Bank for Reconstruction and Development to suspend new lending.