Some waited overnight to get a seat for the ceremony, with the Vatican reporting some 200,000 people in the square and surrounding streets during the ceremony.

"The competent authority informs us that, while the funeral of Pope Francis has ended, more than 250,000 people are present," said the Vatican in a brief statement Saturday at the end of the ceremony.

The crowds, packed with young people, applauded as the pope's coffin was carried out of St Peter's Basilica by white gloved pallbearers, accompanied by more than 200 red-robed cardinals.

Francis was "a pope among the people, with an open heart", who strove for a more compassionate, open-minded Catholic Church, Cardinal Giovanni Battista Re said in his funeral homily.

There was applause as he hailed the pope's "conviction that the Church is a home for all, a home with its doors always open".

Many of the more than 50 heads of state attending the funeral had entered the Basilica beforehand to pay their respects at the coffin of the Argentine pontiff, who died on Monday aged 88.

Guests included Argentina's President Javier Milei and Britain's Prince William as well as Ukraine's Volodymyr Zelensky, who met with Trump shortly beforehand, their first encounter since February's Oval Office clash.

Francis sought to steer the centuries-old Church into a more inclusive direction during his 12-year papacy, and his death prompted a global outpouring of emotion.

"I'm touched by how many people are here. It's beautiful to see all these nationalities together," said Jeremie Metais, 29, from Grenoble, France. "It's a bit like the centre of the world today."

Italian and Vatican authorities mounted a major security operation for the ceremony, with fighter jets on standby and snipers positioned on roofs surrounding the tiny city state.

But after St. Peter's bells tolled, the massive crowd was largely silent, watching proceedings on several large screens around the square.

The funeral sets off the first of nine days of official Vatican mourning for Francis, who took over following the resignation of Pope Benedict XVI in 2013.

After the mourning, cardinals will gather for the conclave to elect a new pope to lead the world's 1.4 billion Catholics.

Simple tomb

Francis died of a stroke and heart failure less than a month after he left hospital where he had battled pneumonia for five weeks.

He loved nothing more than being among his flock, taking selfies with the faithful and kissing babies, and made it his mission to visit the peripheries, rather than mainstream centres of Catholicism.

His last public act, the day before his death, was an Easter Sunday blessing of the entire world, ending his papacy as he had begun it -- with an appeal to protect the "vulnerable, the marginalised and migrants".

The Jesuit chose to be named after Saint Francis of Assisi, saying he wanted "a poor Church for the poor", and eschewed fine robes and the papal palace.

Instead, the Church's 266^th pope lived at a Vatican guesthouse and chose to be interred in his favourite Rome church, Santa Maria Maggiore, the first pontiff to be buried outside the Vatican walls in more than a century.

Catholics around the world held events to watch the proceedings live, including in Buenos Aires, where Francis was born Jorge Bergoglio in the poor neighbourhood of Flores in 1936.

The pope showed us that there was another way to live the faith," said Lara Amado, 25, in the Argentine capital.

Francis asked to be put inside a single wooden coffin to be laid in a simple marble tomb, marked only with the inscription "Franciscus", his name in Latin.

After the funeral, the coffin will be driven slowly in a large white Jeep to Santa Maria Maggiore via the Fori Imperiali, where Rome's ancient temples lie, and the Colosseum.