A row has broken out between the mayor of Rome and the Roman Catholic Church over what should happen to coins retrieved from the Trevi fountain.
Every year nearly €1.5m (£1.3m) is fished out of the famous landmark. It is traditionally given to a Catholic charity to help the destitute.
But now Mayor Virginia Raggi wants the money spent on the city's crumbling infrastructure instead.
The Catholic charity Caritas says the loss of income will hit the poor.
"We did not foresee this outcome," Caritas director Father Benoni Ambarus told Avvenire, the newspaper of the Italian bishops' conference. "I still hope it will not be final."
The newspaper ran a scathing article on the move in its Saturday edition, headlined "Money taken from the poorest".
City councillors have approved the change and it is due to take place in April.
However, many Italians have taken to social media to ask the council to reconsider, the Ansa news agency reported.
Ms Raggi took control of Rome in 2016 for the anti-establishment Five Star Movement, which formed a national coalition government last year.
Her popularity has fallen for failing to tackle the indebted city's issues.
In October, thousands of protesters gathered outside city hall to denounce Ms Raggi for failing to address problems including uncollected rubbish and potholed roads.
The Trevi fountain, nearly 300 years old, is visited by millions of tourists every year.
The tradition of throwing coins was made famous by Frank Sinatra's Three Coins in the Fountain in the 1954 romantic comedy of the same name.
The fountain also featured in the 1960 film La Dolce Vita which saw actress Anita Ekberg wade through its pristine waters in a strapless dress.