Italy has tightened its citizenship rules for descendants of emigrants, limiting passport eligibility to those with Italian parents or grandparents.

Under the "jus sanguinis", or descendent bloodline law, anyone with an Italian ancestor who lived on or after March 17, 1861, when the Kingdom of Italy was created, previously qualified to be a citizen.

Italy's parliament approved legislation on Tuesday that now requires passport applicants to prove they have at least one parent or grandparent who was born an Italian citizen.

Citing concerns over passport "commercialization" and application backlogs, the government defended the rule change as a way to strengthen genuine ties between Italy and its citizens abroad, reported the BBC.

Italian citizens living abroad surged by 40 percent during the past decade, jumping from 4.6 million to 6.4 million between 2014 and 2024, according to government figures.

More than 60,000 citizenship applications remained pending when Prime Minister Giorgia Meloni's government introduced the reform in March.

The foreign ministry has previously defended the reform, stating it "will free up resources to make consular services more efficient, to the extent that they can be dedicated exclusively to those who have a real need, by virtue of their concrete connection with Italy".

"Citizenship must be a serious thing," Foreign Minister Antonio Tajani said, adding that while descendants of Italians would still be eligible, "precise limits will be set, especially to avoid abuse or phenomena of 'commercialization' of Italian passports".

Italy's move to restrict citizenship rules for the descendants of emigrants has sparked an outcry in the United States, which is home to a large Italian diaspora, reported the Financial Times.

The prospect of European citizenship has gained renewed appeal among some US citizens, particularly following US President Donald Trump's reelection.

"People are very upset and frustrated," lawyer Marco Permunian, founder of the Italian Citizenship Assistance consultancy, told the FT. "The Italian-American community has always had a very strong feeling of pride in their heritage and a lot of them took this very personally. A lot of them are preparing to fight this law. They are very motivated and they are not going to let it go."

The US is home to more than 16 million Italian-Americans, whose ancestors emigrated in the late 1800s and early 1900s. US lawmakers have cautioned that Italy's new policy "risked alienating" thousands of Italian-Americans who had "invested significant time, effort and financial resources" in citizenship applications.