At the weekend, a few stone laurel leaves fell from the top frieze of the fountain, which marks the terminal point of one of the aqueducts that brought drinking water to ancient Rome.

Umberto Broccoli, Rome's cultural superintendent, said the damage was "not worrying" and that the detachment was probably due to water infiltration caused by heavy snowfall that hit Rome in February.

Police put barriers around the fountain and restoration experts checked the damage. They removed about five other pieces that appeared to be in danger of falling from the top.

The basin of the fountain, which figured prominently in films such as "La Dolce Vita," "Roman Holiday" and "Three Coins in the Fountain," was to undergo its weekly draining and cleaning on Monday.

Dino Gasperini, Rome city counselor for culture, asked for funds to protect the fountain from any more possible imminent damage and said another full-scale restoration was needed.

The last major restoration of the fountain, whose current form was completed in 1762, was 20 years ago.

While Broccoli said the falls were not worrying, Italy's Greens party said the Italian capital's monuments were in dire condition and announced a campaign where residents can send e-mails to signal dangers to Rome's cultural heritage.

"We think what is happening at the Trevi Fountain, one of the most recognised monuments in the world, is very grave," said Greens leader Angelo Bonelli.

Bonelli said concern for the fountain was even greater because earlier this year a few small pieces fell off of the Colosseum. That monument is now being restored.

Tourists viewing the fountain on Monday expressed concern and said Italy had to protect its cultural heritage.

"Heritage should not be just a cost, it should also be a resource. For example, that bar should pay something more given that it has the privilege to be located in front of the Trevi Fountain, which is one of the world's greatest wonders," said Italian tourist Daniele Masta.

The Trevi Fountain stands at a point where in ancient Rome three roads (tre vie) formed a junction. Water arrived from a source about 13 km from the city and was carried by an aqueduct to serve the populace.

The aqueduct, bringing what was called Virgin Water, served the city for more than four centuries until it was destroyed by invading Visigoths.

The tradition of building monumental fountains at the terminus of aqueducts was revived after the Renaissance.

The current fountain was commissioned by Pope Clement XII in 1730 to replace a more simple basin and completed in 1762. The allegories show Tritons guiding Oceanus, the god of all water, on his shell chariot.

A Roman tradition says tourists who throw a coin in the fountain are guaranteed that they will someday return.

(Additional reporting by Antonio Denti, editing by Paul Casciato)

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