Pope Francis called for "a poor Church for the poor" in an address to journalists from around the world on Saturday, as part of a charm offensive characterised by an informal style in contrast with the Vatican's monumental halls of power.
The newly-elected pope smiled and joked with 3,000 journalists and Vatican communications officials at an audience, as well as imparting a blessing for any atheists present.
The 76-year-old said he picked his papal name at the end of a dramatic conclave on Wednesday because he was inspired by St Francis of Assisi, who was "a man of poverty and a man of peace".
"How I would like a poor Church for the poor!" said the Argentinian with the common touch, the first pope from Latin America and the first non-European pontiff in nearly 1,300 years.
But the former Jorge Mario Bergoglio faced fresh accusations at home that he had failed to speak out about the brutalities committed by Argentina's military leaders during the "Dirty War".
The special audience with journalists in a Vatican auditorium was billed as another sign of the greater openness in Bergoglio's first days as leader of the world's 1.2 billion Catholics.
Francis described the emotional moments of his election in a conclave in the Sistine Chapel on Wednesday, offering a rare insight from a pope into deliberations shrouded in the strictest secrecy.
He explained that when the cardinals elected him, he had been sitting next to Brazilian Cardinal Claudio Hummes, who had comforted him when it became clear he would be the 266th pope of Rome.
"He hugged me and kissed me and told me not to forget the poor. And that word went in here," Francis said, pointing to his head.
"I immediately thought of Francis of Assisi," he said, adding that the 13th century saint had been "a man of poverty, a man of peace, a man who loved and protected Creation."
"Right now our relations with Creation are not going very well," he added.
The Vatican on Saturday said he had also temporarily re-appointed the entire Roman Curia -- the intrigue-filled administration of the Catholic Church -- which has faced growing criticism.
"The Holy Father wishes a certain time for reflection, prayer and dialogue before any definitive nomination or confirmation," it said.
Vatican watchers are keeping a close eye on nominations to top posts as an indication of what changes in substance -- apart from the already evident ones in style -- his papacy could herald.
Analyst Marco Politi, the author of a biography of Francis's predecessor Benedict XVI, has said it is clear that the new pope -- who officially has absolute powers -- will rule in a more inclusive way together with other Church figures.
"The Church will be governed by the pope together with the bishops. That is what we will see in the next months and years," Politi said, adding that he would probably seek to create some "mechanism of consultation" with the world's prelates.
The Vatican said Francis would meet next Saturday with the 85-year-old Benedict, who last month became the first pope to resign for 700 years because he said his physical and mental strengths were failing him.
The two men know each other well and Bergoglio is believed to have been runner-up to the German in the 2005 election, but the pope's style contrasts sharply with that of his more academic predecessor.
Speaking in a folksy Italian, he has urged Catholic leaders to shun worldly glories and lead a spiritual renewal in the Church that will reach "the ends of the earth", or risk becoming little more than a charity with no spiritual foundation.
The Catholic Church has been rocked in recent years by multiple scandals including thousands of cases of abuse of children by paedophile priests.
Catholics have also been abandoning churches in huge numbers in an increasingly secularised West -- in contrast to Latin America, where some 40 percent of the world's Catholics now live.
A moderate conservative in Argentina where he was the archbishop of Buenos Aires, Francis -- the son of an Italian emigrant railway worker -- is unlikely to change any of the fundamental tenets of Catholic doctrine but experts say he could push for more social justice and a friendlier faith.
The Vatican on Friday rejected claims that Francis had failed to protect two Jesuit priests who were kidnapped and tortured by Argentina's brutal military junta during the 1976-1983 "Dirty War", in which 30,000 died or disappeared.
But the Grandmothers of the Plaza de Mayo organisation, founded to help locate children kidnapped during military rule, added to the criticism when it accused him of failing to speak out during the military dictatorship.
"He has never spoken of the problem of people who had disappeared under dictatorial rule, and 30 years have already passed since our return to democracy," said Estela Carlotto, the head of the group, whose daughter Laura was abducted and killed during the military era.
Francis's inauguration mass will take place on St Peter's Square on Tuesday and a million are expected to throng Rome for the celebration.
Several heads of state will come including one who has had a tense relationship with Bergoglio -- Argentinian President Cristina Kirchner, who will also meet the pope in private on Monday.