BOSTON--Mayor Kevin H. White said Saturday the city will ban most vehicles from a large area of central Boston for 24 hours before and during the visit of Pope John Paul II.

The pope plans to arrive in Boston the afternoon of Oct. 1, say a Mass on Boston Common, spend the night in the city, and leave for New York the next day.

The ban will be in effect from midnight Sunday, Sept. 30, to midnight the next day, and the restricted area lies within Mass Ave., Storrow Drive and the Southeast Expressway, White said.

Commercial trucks and vans making deliveries must leave the area by 10 a.m. on Oct. 1. The city will allow cars to use the roads surrounding the area but will prohibit them from entering. Authorities will permit only taxis and buses with special permits to enter the restricted zone, the mayor said.

The ban will "provide the maximum amount of access, safety and convenience to people coming to see the pope at a minimum of disruption to the city," White said. The city is providing more than 1000 parking spaces for buses and is arranging extra off-street space, he added.

The city will provide more than 500 portable toilets and 15 first aid stations to handle the estimated 500,000 people who will attend the Mass, scheduled for 5:30 p.m.