Rome sealed off Trevi Fountain due to crowds of Christmas shoppers.

The sight of large crowds of people doing their Christmas shopping and socialising in major Italian cities is cause for alarm, says Italy's commissioner for the coronavirus emergency, Domenico Arcuri.

Crowds thronged shopping streets in Rome, Milan, Bergamo and Naples on Sunday, with police in the capital temporarily sealing off access to the Trevi Fountain after people did not respect social distancing, reports Italian news agency ANSA.

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Citing the "intolerable" crowds, Arcuri said: "The measures put in place are aimed at preventing a repeat of what happened this summer. We must be careful, because what happened this summer cannot happen again."

"Let's not see any more photos like those of today: we must all prevent the third wave from taking place" - Arcuri said on television programme Che tempo che fa - "It would be difficult to start the vaccination campaign with a new rise of the epidemic curve."

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The Lazio regional health councillor Alessio D'Amato also urged people to avoid gatherings, "otherwise a third wave will be inevitable."

In Rome there is an increased police presence in the main shopping districts, such as the Tridente area around Via del Corso and in the Prati quarter, where officers control the flow of crowds at weekends.

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Police have also been checking that shops are adhering to anti-covid-19 rules regulating the maximum capacity of customers in each premises, as well as patrolling the Porta Portese flea market which reopened yesterday.

Photo credit LaPresse / Corriere della Sera