World leaders have gathered in Rome to attend the funeral and mourn the loss of Pope Francis.

His Holiness died on Monday, aged 88, from a stroke after he completed a short stint in hospital which saw him diagnosed with double pneumonia.

Following a number of days on display at St Peter's Basilica for public viewing, a funeral mass in St Peter's Square to honour the pontiff will be attended by leaders from across the world.

His casket will be carried through the main doors on Saturday for the outdoor funeral, which starts at 10am local time, with massed ranks of foreign dignitaries to one side of the stone colonnade, facing hundreds of red-hatted cardinals on opposite banks of seats.

Then in a world-first for the Vatican, His Holiness's coffin will then be processed through the streets of Rome to its final resting place at Santa Maria Maggiore.

The Vatican says some 250,000 mourners will fill St Peter's Square and main access route to the basilica to follow the ceremony, which will be presided over by Cardinal Giovanni Battista Re.

Pope Francis's funeral is set to break from Vatican tradition in four major ways today.

Shunning the pomp and privilege usually associated with the papacy during his reign, His Holiness's last rites will carry on his wish for simplicity.

Whereas Pope John Paul II's funeral in 2005 lasted three hours, the service on today is set to take just 90 minutes.

The late pontiff also opted to forego a centuries-old practice of burying popes in three interlocking caskets made of cypress, lead and oak. Instead, he has been placed in a single, zinc-lined wooden coffin, which was sealed closed overnight.

And in a further break with tradition, he will be the first pope to be buried outside the Vatican in more than a century, preferring Rome's Basilica of St. Mary Major, some 4 kilometres (2.5 miles) from St. Peter's, as his final resting place.

President Donald Trump and Melania Trump land in Rome to attend Pope Francis's funeral

US President Donald Trump has landed in Rome to attend the funeral of Pope Francis.

He touched down with his wife, Melania Trump, on AirForce One this morning to join more than 150 dignitaries from across the world.

Also attending today will be the Presidents of Argentina, France, Gabon, Germany, Italy, the Philippines, Poland and Ukraine, together with the prime ministers of Britain and New Zealand, and many European royals.

GB News' Georgina Cutler, who is in Rome today, saw mourners queuing through the night with tents and sleeping bags

GB News' Georgina Cutler, who is in Rome today, saw mourners queuing through the night with tents and sleeping bags