Rome is considering limiting access to the Trevi Fountain, one of its busiest monuments, ahead of an expected bumper year for tourism in the Eternal City, city council officials say.

The Italian capital is preparing to host the 2025 Jubilee, a year-long Roman Catholic event expected to attract 32 million tourists and pilgrims.

Under the draft plans, visits to the fountain would require a prior reservation, with fixed time slots and a limited number of people allowed to access the steps around it.

"For Romans we are thinking of making it free, while non-residents would be asked to make a symbolic contribution, one or two euros ($1.1-2.2)", Rome's tourism councillor Alessandro Onorato told Thursday's Il Messaggero newspaper.

On Wednesday, Mayor Roberto Gualtieri called measures to curb tourist numbers "a very concrete possibility."

"The situation at the Trevi Fountain is becoming technically very difficult to manage," he told reporters.

Other cities are facing protests over problems brought by so-called overtourism, including Barcelona and Venice, where local authorities tested this year an entry charge scheme for visitors.

The Trevi Fountain, where tradition dictates that visitors toss a coin to guarantee their return to Rome and fulfil their wishes, has long been a major attraction, even for visiting world leaders.

Completed in 1762, the monument is a late Baroque masterpiece, with statues of Tritons guiding the shell chariot of the god Oceanus, illustrating the theme of the taming of the waters.