The European Commission said last week that Italy's growing public debt broke EU rules, opening the way for a possible disciplinary procedure and a clash with Rome's anti-austerity government.
"No one should be in doubt that we will apply those rules if the criteria are not fulfilled," Moscovici told a news conference.
"So now clearly the ball is in Italy's court. We need to see a credible path for 2019 as well as 2020. We stand ready to take into account any new elements that Italy may put forward, but let's not waste time," he said.
(Reporting By Jan Strupczewski; editing by Philip Blenkinsop)
