Reuters reports that ECB president Christine Lagarde said in an interview published on Tuesday that the European Central Bank has pledged to be "persistent" and will not repeat its past mistake of tightening policy too early.

"The use of 'persistent' (in the ECB's new strategy) is an indication that there cannot be premature monetary tightening as we have seen it in the past," Lagarde told.

She added it was now time to show that "the persistence we have demonstrated" was having the desired effect of reviving inflation in the euro zone.