"Spain maintains all its options and possibilities open," Economy Minister Luis de Guindos told reporters at a meeting of G20 finance ministers in Mexico City.

Asked if the Spanish government was considering putting forward an alternative candidate to Mersch, he said: "I will not tell you either yes or no."

Spain's move followed opposition from the European Parliament, which voted against Luxembourger Mersch because it wants more women in the European Union's higher echelons.