A massive security operation is being organized in Rome for the arrival of U.S. President Bush on Friday evening. Thousands of police officers will be deployed in the city and the air space will be closed as anti-globalization protesters plan to descend on the city to hold a huge rally. Sabina Castelfranco reports from Rome.

Italian authorities have been preparing extraordinary security measures for the arrival of U.S. President Bush in Rome late Friday. The president is arriving from Poland and is expected to meet with Pope Benedict and Italian authorities on Saturday.

Thousands of security officers are being deployed to patrol the streets in Rome. The airspace will be closed to commercial traffic two hours before the arrival and departure of the president's Air Force One. The Rome airspace will remain closed for the duration of his visit.

Authorities have also decided to close schools one day in advance and now many students are likely to take part in a massive anti-Bush and anti-globalization rally planned for Saturday afternoon along the streets of Rome.

Italy's Interior Minister Giuliano Amato said there would be protests against Bush and the United States. He added that he was confident the authorities would be able to face the risks for public order, as a large number of resources were being made available to guarantee security.

Trainloads of people from across Italy are expected to come into the city to voice their opposition to the continued deployment by the U.S. forces in Iraq and to Italy's deployment of troops in Afghanistan.

Organizers of the rally say people will be protesting not only against the United States but also against Italy's military policies.

"The government of Prodi stays in 16 wars in the world, above all in the war in Afghanistan, in the war in Lebanon," said Piero Bernocchi, one of the organizers.

He said protesters are also against the Italian government's increases in military spending and the expansion of a U.S. airbase in the northern Italian city of Vicenza.

Organizers insist they will hold a peaceful demonstration, but Italian authorities say they will be watching carefully to ensure violence does not erupt.

Achille Serra, the prefect or top government official in Rome, said protesters who have their faces covered, or are seen carrying sticks or weapons will be barred from taking part.

Serra has confirmed that the president's stop in Trastevere, a picturesque neighborhood of narrow streets and alleys viewed by some as a security risk, would go ahead as planned.

The prefect did not deny that there are difficulties in how to manage security in Trastevere but he said all efforts would be made to ensure that the visit there would take place in the best possible way.

President Bush will be touring the Basilica of Santa Maria in Trastevere and take part in a roundtable discussion in the nearby headquarters of the Roman Catholic peace group, the Community of Sant'Egidio, which has mediated in a number of conflicts in Africa.

Residents of Trastevere have already been warned there will be no parking or driving in the area until the president's visit is over.