Hotels in Rome have seen a spate of booking cancellations for late pope John Paul II's beatification on May 1 and local officials now say only half the number expected by the Vatican will come.

"On that day there will be one million two or three hundred thousand people around Rome including Romans and concert spectators," Rome's deputy mayor Mauro Cutrufo was quoted by Corriere della Sera as saying.

But the Vatican had said earlier it expected between two million and two and a half million people to arrive in Rome for the ceremony that will put John Paul on the path to sainthood and during which his coffin will lie in state.

Cutrufo, who is in charge of tourism in the city, said Saint Peter's Square can only contain around 300,000 people and giant screens will be set up at an ancient Roman arena, the Circo Massimo, and in the Piazza San Giovanni area.

Giuseppe Roscioli, head of Rome's hotel association, said the cancellations had come in the wake of the earthquake and tsunami in Japan and the escalation of military operations in Libya, Corriere della Sera reported.

He said there had been "a lot of cancellations as expected" from Japanese visitors and added that a prolonged crisis in Libya "risks keeping tourists from the United States and Southeast Asia away from the Mediterranean."