A celebration that had been planned to take place in Rome's Piazza Venezia on 4 June to mark the 60th anniversary of the liberation of the city from Nazi occupation has been moved to Sunday 6 June. The mayor of Rome explained that the change of plan was necessary because of the visit of the United States president. The visit of George W Bush will place exceptional strain on the police force who will not only have to maintain public order but must guarantee the safety of the visiting president.