The interview came after a mini-summit on the competitiveness of the European economy wrapped up in Berlin, in an event that was, attended by German Chancellor Angela Merkel and French President Francois Hollande.
Notably, Renzi never received an invitation to be in attendance at the gathering, which Fabio Massimo Castaldo said is not the news.
"I think that Renzi cherished the hope that after the UK's withdrawal from the EU, Italy would be able to become the third leading country in the European Union; it seems he believed that France and Germany would want to share power with Italy," Castaldo said.
"However, all this is far from reality. On the one hand, Brexit led to the strengthening of the France-Germany alliance, and on the other, the Renzi government never inspired confidence and its stand was repeatedly ignored," according to him.
He described Renzi as a victim of his own permanent promises, a man who constantly changes his position, including on the issue of the anti-Russian sanctions.
"After getting no invitation to the summit of European leaders in Berlin, Renzi should force the EU to hear the voice of Italy, something that is in line with his interests ahead of the Italian referendum on the reform of state power, scheduled for December," Castaldo said, adding that "right now, no country in Europe does not see the position of Italy."
"Renzi should find courage to offer more decisive steps, for example, to veto the extension of the anti-Russian sanctions. Alas, this will never take place because Renzi has repeatedly showed a willingness to adhere to the logic of a more powerful player and succumb to the oversea pressure, he said in an apparent nod to the United States.
Castaldo also lashed out at what he described as "Renzi tales fit only for the pro-government media."
He recalled that this year, the statistics showed that Italy's economic recession and budget deficit have grown more than expected, and that the implementation of the public administration reform and the program to cut spending leave much to be desired.
"All this cannot but damage the credibility of Italy in the context of a unified Europe, and the result was not slow to arrive," he concluded.
It is worth noting in this context that on August 22, Renzi, Merkel and Hollande held a meeting on the Italian island of Ventotene to discuss the consequences of the Brexit vote and how to shape the future of Europe.
While Angela Merkel is likely to conduct a "cementing" policy of strengthening ties within the remaining 27 member block, Italy is eager for greater European consolidation.
The EU is currently facing the risk of another secession referendum in Netherlands, which may be well followed by other countries.
Germany also opposes any attempts to confront existing deficit and debt constraints, but France and Italy, which have troubles achieving the specified figures, call for expansionary measures and reduced economic austerity.
