"Italy is starting once again to play the role that it normally does in Europe as one of the three major founder countries and economies," Gentiloni said in an interview with La Stampa Daily.
"It is crucial that this new beginning sends a strong message to Italian citizens that Europe is not a problem but is our only future, looking at the world in the coming decades," he said.
Italy's centre-left -populist government that took full power last week has "a clearly pro-European orientation" and has already announced it will be at the forefront of countries working to cut CO2 emissions, he said.
"My role will be to try and make the instruments that serve the entire EU work optimally, including budgetary policy, the monetary system, investments, taxation and social policy," said Gentiloni.
On the key issue of migration, he confirmed he would work within the EU executive to reform the bloc's current asylum rules and on safeguarding its borders, as well as to help countries of origin. Italy "can make an important contribution" in this area, he said.
Gentiloni is due to take up his post in November, when the new European Commission takes office. Italy's former premier, he is a member of the centre-left Democratic Party, one of the parties in Italy's new coalition government.
Taking on the European Commission post will be "a big responsibility", Gentiloni wrote on Facebook on Monday.
"I will be guided by two principles - to build agreement within the College of Commissioners and to push for the European Parliament and the European Commission to play a key role together," he said.
In the interview to La Stampa, Gentiloni said the EU plans to introduce a tax on digital services should there be no global accord on a "web tax".
He also said he would also oversee European efforts to harmonize corporate taxes across member states and review the bloc's current regulation on energy taxation.
The EU needs "economic and budget policies that drive growth," Gentiloni told La Stampa, praising the European Central Bank's monetary policy but saying that it was not enough to counter a slowdown.
The new administration led by Premier Giuseppe Conte is widely expected to smooth relations with the EU which were often tense during Italy's previous coalition between 5-Star and the far-right, eurosceptic League party, which collapsed last month.
( With inputs from IANS )