The Vatican Thursday said it was shocked at what Paraguay's decision to cancel a meeting between Pope John Paul II and an opposition political group next week.

The chief Vatican spokesman, Joaquin Navarro, said the action announced Wednesday by Paraguayan President Gen. Alfredo Stroessner, Latin America's longest-ruling military chief, hindered "the exercise of the pastoral mission of the Holy Father."Stroessner cited grounds of security for canceling the meeting, scheduled for Tuesday in the Paraguayan capital of Asuncion. He also charged the group would use a religious encounter for political ends.

The group, called Constructors of Society, has about 350 members and includes politicians, peasant farmers, Catholic laymen and lawyers.

It was the first time in John Paul's 37 trips abroad that a foreign statesman interfered with his schedule. But the church in Paraguay said it would try to switch the meeting site from a government-controlled site to one under direct church control.

Thursday morning, John Paul traveled from Cochabamba in central Bolivia, to Sucre, another centrally located city, known for its Spanish-colonial architecture and its many churches.

Crowds lined five deep to welcome the pope along a 2 1/2-mile motorcade.