The choice of Gentiloni was a surprise move by Ursula von der Leyen, the incoming head of the European Commission, who named her new team of top officials from a list of nominees proposed by all EU member states apart from Britain.
Gentiloni will take over from Pierre Moscovici, a former French finance minister who spent most his five-years as commissioner in battle with Italy over its colossal debt and chronic overspending.
Pierre Moscovici. Photo: AFP
The EU has strict rules on public spending, with countries expected to deliver national budgets with deficits that do not exceed three percent of GDP with debt not over 60 percent.
Italy's public debt currently stands at a daunting 132 percent of GDP and the new government in Rome will struggle to meet belt-tightening commitments already made to Brussels, potentially leaving Gentiloni in the delicate role of enforcing rules against his own country.
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Rome's new government, which brings together the anti-establishment Five Star Movement (M5S) and the centre-left Democratic Party, has indicated that it wants to pursue an "expansive" economic policy, but "without jeopardising" sound public finances.
Plans tabled by Italian Prime Minister Giuseppe Conte include a demand to reform the EU budget rules, a gambit that will face fierce pushback by Germany and the Netherlands that cherish balanced budgets across Europe.
In introducing her new team on Tuesday, von der Leyen described Gentiloni as "very experienced".
"He knows the difficult issues we face," she added.
According to her organisational plans, Gentiloni will be overseen by Valdis Dombrovskis, a former Latvian prime minister who returns to the commission as Executive Vice President over economic affairs.
The politically right-of-centre Dombrovskis held a similar role in the last commission and was often tussling behind the scenes with Moscovici.
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