At a huge outdoor mass in a city that represents Venezuela's industrial future, Pope John Paul II vigorously defended workers' rights and lashed out at the enormous differences in wealth in Latin America, where shacks alternate with skyscrapers.

John Paul was speaking to an audience estimated at close to 100,000 people at the new city of Ciudad Guayana in eastern Venezuela, center of the country's important aluminum and steel industries. But his message was for employers and all workers, particularly in developing countries. "How much longer will man and men of the Third World have to support unjustly the primacy of economist principles over inviolable human rights?" he asked.

John Paul called "horrifying" the imbalance between the few rich and the many poor in many parts of the Third World which, he said, called for radical reform -- based on fundamental respect for workers.

A better symbol of Venezuela's hopes and failures -- and the skewed distribution of wealth attacked by the pope -- would be difficult to find. A new city, Ciudad Guayana overexpanded during Venezuela's oil boom when the country strove to use oil profits to break its oil dependency, by developing the region's rich iron ore, aluminum, bauxite and hydroelectric energy resources. When bust followed boom, the city was caught unprepared.

Now rows of unoccupied apartment buildings, paint peeling, line the site of the pope's mass, waiting for middle-class buyers. Meanwhile, workers from Sidor, the huge state-owned, heavily indebted steel mill, live in shacks along the banks of the Caroni River, unable to afford decent housing.

John Paul called for cooperation between labor and capital instead of class struggle to resolve differences between the two, adding that the legitimate demands of workers should however take into account the "limits imposed by the country's economic situation."

[Meanwhile, Reuters news agency quoted San Salvador's Archbishop Arturo Rivera y Damas in Maracaibo as saying that Pope John Paul, while supporting the local church's mediation in El Salvador's civil war, has made no mention of a papal initiative. The auxiliary archbishop of San Salvador, Gregorio Rosa Chavez, said Sunday in San Salvador that the pope had offered Vatican help in the negotiations.]