A huge crowd cheered as Pope Francis, in his first international trip as pontiff, walked onto the tarmac in Rio de Janeiro, Brazil to begin a weeklong journey in the world's most populous Roman Catholic nation.

The Argentinean-born pope, who has made a name for himself as a humble, unassuming pontiff, was greeted with applause, a choir and a bouquet of flowers.

Brazilian President Dilma Rousseff waited on the tarmac for the pontiff to step down the stairs from the no-frills commercial airliner that was specially booked for him.

Once on the streets, frenzied crowds of Roman Catholics mobbed the car carrying Pope Francis.

Ecstatic believers forced the closed Fiat to stop several times as they swarmed around during the drive from the airport to an official opening ceremony in Rio's center. A few security guards struggled mightily to push the crowd back in scenes that at times looked alarming.

Francis, however, looked calm. He rolled down the window on the back passenger-side of the car where he was sitting, waving to the crowd and touching those who reached inside. At one point, a woman handed the pontiff a dark-haired baby, whom he kissed before handing it back.

After finally making it past crowds and blocked traffic, Francis switched to an open-air popemobile as he toured around the main streets in downtown Rio through mobs of people who screamed wildly as he waved and smiled. Many in the crowd looked stunned, with some standing still and others sobbing loudly.

Idaclea Rangel, a 73-year-old Catholic, was pressed up against a wall and choking out words through her tears. "I can't travel to Rome, but he came here to make my country better ... and to deepen our faith," she said.

At the airport earlier, Brazilian President Dilma Rousseff vigorously shook Francis' hand after he descended the stairs following a no-frills commercial flight that arrived about 4 p.m. He made no public statements.

Reaching the end of the red carpet full of church leaders and other dignitaries, Francis and the Brazilian president paused to be serenaded by a choir of about three dozen young people singing an anthem linked to World Youth Day, a semi-annual event uniting hundreds of thousands of young faithful from around the globe. Before singing, the kids robustly yelled soccer-like chants in the pope's honor.

During his stay, the 76-year-old pope will meet with legions of young Catholics converging for the church's World Youth Festival in Rio. More than 1 million people are expected to pack the white sands of Copacabana for the Mass celebrated by Francis. He will also visit a tiny chapel in a trash-strewn slum and make a side trip to venerate Brazil's patron saint, Our Lady of Aparecida.

Earlier on the flight from Rome, Francis expressed concern for a generation of youth growing up jobless as the world economy sputters. He warned about youth unemployment in some countries in the double digits, telling journalists there is a "risk of having a generation that hasn't worked."

Brazil and much of Latin America is a region with more faithful than any other in the world, but millions have left the church for rival Pentecostal evangelical churches or secularism.

A poll from the respected Datafolha group published Sunday in the newspaper Folha de S.Paulo said 57 percent of Brazilians age 16 and older call themselves Catholic, the lowest ever recorded. Six years ago, when Pope Benedict XVI visited, a poll by the same firm found 64 percent considered themselves among the faithful. In 1980, when Pope John Paul II became the first pontiff to visit Brazil, 89 percent listed themselves as Catholics, according to that year's census.

Pentecostal evangelicals stood at 19 percent of the population in the latest poll, rising from virtually nothing three decades ago by aggressively proselytizing in Brazil's slums.

Based on reporting by The Associated Press.

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