More than 160 delegations of states and territories, international organizations and religious representatives from across the world along with 1 million people were expected to attend Tuesday's inauguration of Pope Francis in Vatican City, local reports said.

The U.S. Vice President Joe Biden, a practicing Catholic, flew to Rome at the weekend as well as Argentina's President Cristina Fernandez de Kirchner and Brazilian President Dilma Rousseff.

Chilean President Sebastian Pinera was also in Rome and attended first Sunday prayers of the Argentinian pope, while Mexican President Enrique Pena Nieto's arrival was also expected.

German Chancellor Angela Merkel, French Prime Minister Jean-Marc Ayrault and his Spanish counterpart Mariano Rajoy were among European leaders set to attend, along with the European Commission President Jose Manuel Barroso and European Council head Herman Van Rompuy.

On Monday, Francis, the first pope from Latin America and the first Jesuit, held an official meeting with Kirchner. Relations between the two have been tense in the past, particularly over the issue of poverty.

Francis became the 266th pope in the Catholic Church's 2,000-year history last week. He said that his name was inspired by one of the most humble and respected Catholic figures, St Francis of Assisi.

According to local analysts, there were high hopes that Francis, who has shown a particular interest in making common cause with the poor in society, will contribute to bringing a new period of peace around the world.

The 76-year-old has called for a "poor Church, and for the poor." He has warned cardinals against worldly glories, and has said that the Church could crumble away "like a sand castle" without spiritual renewal.