Spanish Economy Minister Nadia Calvino, who will chair talks among EU finance ministers later Thursday, has told them to prepare for a late night as they aim to conclude a political deal on new EU fiscal rules.

Calvino said that she was aiming for a political deal on the rules at the working diner tonight, which would "balance" the need for sustained debt consolidation and investment in the years ahead.

The ministers remain split on a number of issues. A spat between France and Germany over whether to use the primary or the structural deficit measure in the corrective arm of the rules is thought to be the biggest of the remaining outstanding obstacles to agreement, with each side regarding this as a potential dealbreaker, although there are other open issues.