ROME: Pope Francis was laid to rest in Rome Saturday after a Vatican funeral for the `pope among the people` attended by hundreds of thousands of mourners and world leaders, including US President Donald Trump.

Around 400,000 people packed St Peter`s Square and lined the streets in Rome to say goodbye to the Argentine pontiff, a champion of the poor who had led the world`s 1.4 billion Catholics since 2013.

After a solemn funeral in front of hushed crowds, Francis`s plain wooden coffin a testament to a life of humility was driven slowly to Rome`s Santa Maria Maggiore church, where he will be interred in a private ceremony.

Fourteen white-gloved pallbearers carried the coffin into the church, as children placed baskets of flowers at the altar and a choir sang prayers.

The marble tomb of the Catholic Church`s first Latin American leader is inscribed with just one word: `Franciscus`, his name in Latin.

`An open heart` Francis, who died on Monday aged 88, 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 homily.

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

Red-robed cardinals and purple-hatted bishops sat on one side of the altar in St Peter`s Square during the funeral, with world dignitaries sitting opposite.

In front of the altar lay the pope`s simple cypress coffin, inlaid with a pale cross.

`Bridges not walls` 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 aged under 80 will gather for the conclave to elect a new pope from among their number.

In the homily, Battista Re highlighted Francis`s incessant calls for peace, and said he urged `reason and honest negotiation` in efforts to end conflicts raging around the world.

``Build bridges, not walls` was an exhortation he repeated many times,` the cardinal said.

More than 50 heads of state were present at the funeral, including Trump, who met several world leaders in a corner of the basilica beforehand, notably Ukraine`s Volodymyr Zelensky, in their first face-to-face since their Oval Office clash in February.The White House said Saturday that the president had a `very productive` meeting with Zelensky before the funeral.

Kyiv published a photo of the encounter, the two men sitting face to face in red and gold chairs in the basilica, as well as another showing Zelensky huddled with Trump, Britain`s Keir Starmer and French President Emmanuel Macron.

Trump`s predecessor Joe Biden also attended the funeral, alongside UN Secretary General Antonio Guterres, Germany`s Olaf Scholz, Italy`s Giorgia Meloni, and Lebanon`s Joseph Aoun.

Israel angered by Francis`s criticism of its conduct in Gaza sent only its Holy See ambassador.

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 strove for `a Church determined to take care of the problems of people and the great anxieties that tear the contemporary world apart`, Battista Re said.

`A Church capable of bending down to every person, regardless of their beliefs or condition, and healing their wounds`.-AFP