Letta’s comments come as the EU faces potential turmoil from a rise of nationalist parties across Europe.
He said the success of the economic bloc was crucial but would depend on the “good will” of the remaining 27 member states.
Italy itself has been at the center of this instability, having held a referendum on reforms to parliamentary powers late last year.
The Italian public voted against the reforms, prompting then Prime Minister Matteo Renzi to step down. The country is due to hold a general election in 2018, however, the country faces continued uncertainty in the interim, said Letta.
“I think we have to be a little bit worried. I hope a more wise approach, unity, can take place,” he said.
“If not, I start to think that the country (will see) big legislative instability. I think we have to push for more unity and less fragmentation today.”
